Become a tactical beast with these puzzles:
https://lichess.org/study/tmKbmWaZ
Also stop playing blitz and start playing "Daily" games (1 day per move)... if it's too slow.. just add more concurrent games. Lots of great tournaments here on chess.com... join your countries club and play in teams too.
Looking for a puzzle book containing problems that are 5+ moves deep.. or a generally difficult puzzle book... compositions are also welcome if they arent a pure endgame type
I'd recommend the Informant modules from Chess King Training. I haven't used them myself, but the problems are bonifide rated.
Informant 1 are problems rated about 2000 FIDE
Informant 2 are problems about 2200 FIDE
Informant 3 are problens about 2400 FIDE
Those are purchased seperately from the subscription.
And then there are chess compositions. Well over 100,000 chess compositions have been created since the 1800's, ranging in difficulty from something an average chess player could puzzle out, to dasterdly creations that would drive a GM batty.
Looking for a puzzle book containing problems that are 5+ moves deep.. or a generally difficult puzzle book... compositions are also welcome if they arent a pure endgame type