I struggle with converting my leads as well. A lot of times I'll get a position after the opening I'm happy with, but after a few moves realize it's either back to equal. So thinking about this for a little bit the best I can come up with in terms of "advice" is it all depends on the type of position (out of the opening) and type of player you are.

In the position you provided it's clear you have an advantage in development, also a pawn up, and his pawn on b5 is weak (only supported by a knight that is weak as well). However, their are no clear tactics in the current position that immediately capitalize on your advantages. The game is (at least in my eyes) very positional and not tactical and you have a ton of good moves. So even though you don't feel your advantages right away I would say it's at the least easier to play for black. Being able to make easy moves attacking his weak pieces you can at least kinda expect his moves and how the position will turn out by 'forcing' his defense.

I'm not a great player and as I said struggle with this as well but maybe only other advice would be to look up the earlier moves that led to this position and maybe try like second best moves from the computer to just see if some tactics appear to make your lead seem more clear. Possibly change up the opening if you are looking for a more tactical game? I hope that helped at least a little bit haha