In order to improve I would recommend:
Free:
-
watching how
streamers play and trying to grasp the idea how they think about the game, about different spots etc. (
https://www.twitch.tv/santazzzua (content in Russian only though));
-
engaging in discussions about strategy, hh etc. here, in 6+ group at discord and other places;
-
Reviewing own hands and trying to judge them critically - could you have played this spot any different, what would you have achieved then etc.
-
Trying to find study partner who wants to study the game also and plays similar stakes as you (different opinions and perception always is good).
Paid:
-
Preflop GTO charts (should be mandatory purchase if taking game even a bit serious);
-
HUD, if playing @ PS (should be mandatory purchase if taking game even a bit serious);
-
Strategy video's;
-
Coachings
Then for more advanced players, I would recommend:
- starting to study GTO (multiway Solver, preferably) or at least GTO+ (not very expensive, HU solver)
Hope this helps!