How to get better at chess fast?

Hi, I'm Thomas. I'm a student and I love playing chess. Now I'm an Intermediate player (1500) and I want to be an Advanced player (1900), get better at blitz chess and after that, is BULLET CHESS. So what I can do?

I played lots of rapid games and analyzed them on lichess.org to collect mistakes and blunders, so it makes a lot of sense. But one of the PROBLEM I just REMEMBER from the game that I analyzed in a short time and then, I forgot.

This's one of my games

In moves 54. ...Kh6?? I'm not careful and used premove, so I lose.

I played the Sicilian Alapin that I learned from GothamChess and a lot of other channels. For some reason, I'm NOT CAREFUL and trade of my bishop when 10. Qh4 so my king is outside the center. After some moves, I lose 2 PAWNS and their bishop and rock are both attacking my king with their bishop captured on a7. It's HARD to move in the game's endgame!

You can watch more of my games on my account below. Thanks for reading this. If you have any ideas to improve my chess skills, please comment below.

My account: PhongN_0102