Oh yeah dude, it's Clearly that you are placed on incompetent teams, not that you got placed way the fuck higher than you should have been and that you're getting stomped as a consequence.
https://i.gyazo.com/477c5e54848f0a13e92855cb79d9be55.png
This is, as far as I can tell, your first season of playing Ranked in league. See, this is how Ranked works.
Placement games have a massive effect on your MMR than other games, and subsequent matches (up to about 20-50, no numbers are precise) have an additional effect on your mmr losses/gains, but not to the extent that provisionals do. Provisions easily win/lose you 100 "effective" LP per game, and subsequent wins or losses will cause this number to increase, so 3 wins in a row you could "win" 150 "effective" LP per game, more or less. Again, no precise numbers.
The bottom line is that since you are on a completely fresh account that has never played ranked, you are automatically played at the 50% mark. This is around silver III, 50% of the players in all of league of legends are at or below this line, at least theoretically. The real number is that about 61% players are at or below silver III. We'll get to the significance of that in a moment.
Riot uses an altered form of ELO system, which basically gives and takes hidden MMR value to determine your matchmaking, and as I explained how provisionals work above, those games are extremely weighted in their overall value. If you win several of those in a row, even if you got completely shit on and your team carried your ass like a creepy old ginger carrying a young blonde woman, it doesn't matter, the wins and losses are all that directly affect your elo or MMR.
So what likely happened is that you are, really, somewhere in bronze. Maybe mid-high bronze, but still bronze. Now, believe it or not, even at the lowest levels, there is a significant different between 4-5 divisions. Very significant. The players above you may still be completely dog shit at the game, but they aren't as bad as you, theoretically. MMR is designed to try and get you to an even 50% winrate. If your winrate is extremely low (as yours are, let's be frank) your MMR will tank so you play easier players - players near your skill level. The average player who plays where they belong fluctuates an average of 1 division, 2 at MOST. This is while maintaining a near-average winrate of around 50% (maybe 49%, maybe 51%.)
Players who are playing where they belong simply do not lose 60-70% of their games under any circumstances. You have played more than just a couple games, so this percentage result is not indicative of sample bias due to poor sample size - variance has a much greater impact in lower amounts of games from a statistical standpoint.
Thankfully, we are not robots. We are humans, and we can reason the possible causes for your statistical irregularity.
Now to preface my following statements, I'm not rank shaming you. I'm just saying that you are bad at the game. This doesn't make you a bad person, you just need to get over it.
In your primary role, you have an average winrate of 32%. This is extremely low, and near the bottom-limit for winrate. Statistically, you should NEVER have lower than a 25% winrate, because statistically even the WORST players who are trying to win the game will not be able to feed enough to prevent their team from winning the game in 25% of their games.
(explaining above statement)
Using statistics, we can state that:
You have a 25% chance of having 2 winning lanes, 50% chance of having 1 winning and 1 losing lane, and 25% chance of having 2 losing lanes.
So 25% of the time, even if you're losing hard, your team should always be able to carry you if you're trying to win the game. This also means that unless someone is smurfing or getting boosted, you should never have a higher than 75% winrate at the game.
You are rapidly approaching that 25% winrate threshold.
If your claim of "bad teams" was accurate, then your stats wouldn't be as bad as they are. In most games on a non-braindead farm champ (Sivir) you average 3-5 cs per minute. This is Atrocious. Again, you're not a horrible person, you're just bad at farming. Farming for an adc is a huge indicator of skill. Players in silver usually average about 5 cs, though this varies more by champion choice than other ranks do. When you're doing poorly, you often gain about 3 cs per minute, which means that you miss almost 70% of your farm. That's an insane amount, and even more indicative of your skill because your games are short.
You also have a ton of deaths which also indicate that you are incapable of playing safely and aren't sure of why you're dying or understanding the significance of your death - all these things tell me that you're extremely tilted, even more so because you post here claiming that your teams are holding you back.
Elo hell doesn't exist, because statistics when properly curated, don't lie, period.
Now it's not entirely your fault as to why you got placed as high as you did. As I mentioned earlier, a little over 60% of the players in the game are at or below Silver III, which means that it really shouldn't base your MMR at Silver III, more like Silver IV, or in my opinion, Silver V. As a new player in ranked you got thrown above your head playing against people who are significantly better than you, and the statistical basepoint used by league's provisional system for new accounts is inaccurately calculated, at least for modern seasons. It's extremely possible that the worst players got worse and the better players got better as the game goes on because extremely bad players aren't usually serious about improving, and the competitive nature causes them to quit, this means that lower ranks are much more likely to contain extremely new and under educated (game knowledge wise) players.
You're lucky though! Once you play a bunch more you'll demote and land where you need to to be able to play against players that are just as good (or bad) as you are! And next season during provisionals, it will use YOUR OWN MMR to base your provisional placement instead of a generalized curve! This means that you'll have much more fair games in provisions next season, especially if you hop back on the horse and play some more!
If you're worried that you don't 'belong' where you are - then change it. Play more, perform better. Don't worry if you don't though. Everyone is bad to some extent, some more than others. That's okay though, being bad and acknowledging our faults makes us better at the game. There are plenty of resources available to help you, sites to help you get your runes and masteries straightened out, to answer questions, and to build fundamentals to the game. Places like Lol-coaching.gg, Op.gg, Youtube, /r/SummonerSchool, and tons of other places.
I encourage you to look to improve instead of scapegoating your team. I know it's hard when you're frustrated about your current performance and progress, I've been there. I'm currently Platinum 3, and I was in my Platinum 1 promotions last season. Want to know a secret, though? In season 2, I was in Bronze V. Bronze was way worse then, too. I had something like a 37% winrate, I mained Ezreal ADC, and I was bad. Really, really, really, really bad.
There's plenty of videos showing how awful I was at the time, like this one where I thought Jax's third auto attack was actually crit RNG. I didn't kite, I didn't use all of my spells, I just facetanked all of his damage. And that's just a small sample! Remember, no matter how good you are, there's always someone better than you. And no matter how bad you may be, there are always several people worse than you.
Play to improve, and you will climb.
TLDR;
Basically, you got carried in your provisionals and got placed way higher. This was exacerbated by Riot's provisional systems. You should NOT have been played in mid or high silver, but probably mid or high bronze, perhaps lower. This is indicated by your winrate over ~30 games and performance in those games. Your MMR slingshots back and forth during your first 50 games or so after your provisionals and that's why you see such a large variance in the skill of the players you play against.