Honestly, challenger streamers will even say it all the time, it all comes down to mentality and game knowledge.
If you're talking professional players, they don't just sit there and practice solo que everyday and have some god-given talent. They know the ins and outs of everything. How much damage they can do at any moment because they've memorized the scalings/ratios/base damages/cds, and know how and when to wave control or rotate to gain small advantages. Their micro-mechanics are so accurate to the point where you'd have to slow the video down to see exactly what they did. Of course, for all of this you need to think fast and click fast. But above those is to have the game knowledge to begin with.
Then its the mentality. Don't get tilted by everything. Trolls are unavoidable. Inters are unavoidable. Afkers are unavoidable. Just laugh about it and que up again. In-game you need to know that just because all lanes are pushed to your inhibs it doesn't mean all hope is lost. Scrap together what you can get and build up your comeback. etc. etc. etc. I'm sure you've heard it all before.
I guess if I were to actually give you some proactive advice, if you really want to get better, record your games. Watch streamers/pros whatever and then after you play some games watch your own recordings. Observe and critique your own mistakes and see what kind of mindset made you make those decisions in that moment
Good luck!