?
As 800-900, what should I focus on in chess?

I'd say like learning all of the "good" openings and honestly just try to slowly start mastering middlegame and endgame tactics.

Learn exactly how to think in the opening, middlegame and endgame — this is what I teach.
Always blunder-check your moves.
Solve tactics in the right way.
Analyze your games.
Study games of strong players.
Learn how to be more psychologically resilient.
Work on your time management skills.
Get a coach if you can.

Learn exactly how to think in the opening, middlegame and endgame — this is what I teach.
Always blunder-check your moves.
Solve tactics in the right way.
Analyze your games.
Study games of strong players.
Learn how to be more psychologically resilient.
Work on your time management skills.
Get a coach if you can.
Thankfully, I have a coach.
As 800-900, what should I focus on in chess?