You most likely need to watch more people play, and preferably someone who explains why they are making the decisions they are making. Watching people play helps in general, but understanding their thought process makes it easier for you to identify these things in your games.
Check out youtube channels like Foxdrop, Phylol, SoloRenektonOnly, and Anklespankin. All of them try to explain what they are doing
I would highly recommend Prismal. He streams on Twitch and occasionally posts Youtube videos. He isn't as consistent as the ones I mentioned above, but he's a Challenger, so he has a ton of knowledge that most of us don't have. Below are two videos that he did with Anklespankin that eventually lead him to start streaming/recording. He offers a ton of information that kinda makes your head spin the first time watching it, but it makes sense when you actually stop and think about it. If you catch him in a stream, ask if he'll do an informative stream, cause he'll explain everything going through his head while he plays. To preface this, these videos are kinda old now, but you can see how much information he provides during the game.
https://youtu.be/wjxRYyISdr8
https://youtu.be/usp28UvZLsY
I assume you are trying to get Gold for rewards, so this piece of advice probably won't help you right now, but I'd recommend making a second account. We tend to really put a lot of pressure on ourselves when playing on our main account, so by playing on a side account, you'll be more relaxed about a loss and maybe learn to not tilt as much.
I managed to get my main account to Gold 5 and sorta panicked when I lost a few games which put me at 2 lp, so I stopped playing ranked on it. However, I still wanted to play League, so I started playing Ranked on the account I made to teach a friend the game. I ended up getting Gold 3 on that account in about a 1/7 of the games I had on my main. Some of that is my MMR on the new account wasn't so screwed up from me learning, so I was able to climb faster. I also think some of it is because I already knew I could get Gold since I was Gold on my main, so I wasn't as worried when I got to promos like I had been on my main. Additionally, that wasn't my main account, so when I was placed Bronze 1 after placements, I mentally knew that wasn't my true rank and didn't let it intimidate me.
In the new season, you might considering starting out by playing on a second account so you can learn, and then playing on your main when you feel like you know stuff. You won't mess up your MMR on your main that way while you learn the new Runes, and you'll be a little more relaxed because you aren't ruining your main account if you lose a few games.
I also highly recommend watching videos on other roles as well. You play a lot of Jungle, which means you can affect the whole map. If you understand your lanes, you'll be able to help them more. SoloRenektonOnly is a top laner and he'll talk about how Junglers don't know what to do when a laner dies, that they half push a wave instead of freezing it when their laner dies which puts the laner even further behind, how they don't recognize that a lane will be pushing to your team in a minute which is a perfect gank opportunity, or that he set up a freeze and thus can't really respond if his jungler is invading or being invaded.
Again, low elo players aren't as aware of these things, but if you can see it, you can start to predict what the enemy would do and maybe help save your team. If your top laner is pushing, maybe you need to be near top to help countergank. Do you see that the enemy bot lane is a Caitlyn or Trist, they'll probably push, so when you see the wave around mid, look at see which way the lane is pushing and see if you can gank them just to relieve some pressure from your laners. Is there a mid lane bully like Syndra, she will probably be pushing/poking so your lane might need you to come to lane to scare her off so they can waveclear and back without losing too much CS.