The fastest way to improve is to study your own games. As soon as a game ends, think for yourself before switching on the engine: where did the game turn, on which move were you unsure?
Then use the 'Analyze the game' button on the game screen. Look at the moves marked with a question mark and ask yourself for each one: why did I play this, and what did I miss?
Write your mistakes in a notebook and sort them by type: tactics, time, opening or endgame? Work on whichever type comes up most often.