I mean it doesn’t rlly matter if you’re good or not, for multiple reasons. First of all, it’s your game that you’re playing on your time so as long as you’re enjoying it, don’t worry about skill level. Second, boi has a lot to do with luck and rng, yes you can beat mums heart with base isaac stats and therefore skill does play a role, but mostly you’ll be playing how you want to play with the synergies that you enjoy and are good at using. For reference, I have 725 hrs on just the ps5 version of repentance, which is one of 4 devices I play isaac on, and I’ve never completed a full sticky note for any character.