I am playing chess for 3 years .My rating is 640 here. How to improve?

You should play classical games. It gives you a lot of time to think.

I got 900 rating.

hey you can also join team value of pawns for some training

@Esteban_Rosas_Neri said in #31:
> You shoul play with professional players but with friendly rounds, and then you can study all the things that they gives to you and then you can use them in your important games.
How? It's really hard to play with proffesionals even for players 2000+ here.