How do i improve at chess?

You improve the same way you do it at school. The moment you quit studying, your rapid progression will slow down.

@ChessMathNerd Your daily routine seems to take 2-3 hours, right?

Had to go to Bundeswehr. (Military Organisation)
There I learned... ah, forget it. Make your own way :-)

Study openings ;-)

@Alakaluf Yep. It takes time to improve at my level.