Why am I losing so much more often with black (newer player)? I have played about 125 games so far online and am rated 834 in rapid (I did play a lot as a child but not in many years) and I have double the win percentage with white pieces that I do playing as black. Is there any logical reason to this other than some confounding factor I'm not thinking of? I know that white does win slightly more often than black at higher levels and the engine favors white from the outset. However, I think 72% win rate with white and 37% win rate with black is quite drastic. Maybe 125 is too small a sample size and my stats will regress to the mean as I play more, but I actually feel like I'm doing something wrong with black. Almost a feeling of discomfort and constantly responding rather than making plans. Can someone give me some advice on a different way to look at playing with black?
My only theory is that while I don't play with any specifically named openings with either side, I do begin every game along the same lines with white, so maybe I am playing a commonly used opening with white and my opening with black is just not optimal.
It's hard to say without analyzing your games but I imagine there are two parts of your problem.

General lack of opening principals

Investing time in learning concepts like &quot;what is the goal of the opening&quot; can be just as valuable as practicing tactical puzzles. Openings aren't just about memorizing move sequences but there are plenty of general concepts that can improve your game.

Lack of confidence specifically with black

You might subconsciously discount black's ability to play great games. You could look up some grandmasters game analysis videos where black wins for some inspiration. You can find some incredible presenters online.
You also might want to consider changing up the opening systems you play. I imagine you mostly play a lot of e4 e5 games. Consider learning a little bit about openings like the caro-khan or the French. With a little preparation you'll catch a lot of new players by surprise. Even without prep chances are you'll be taking your opponents out of their comfort zone too, hopefully that can even the playing field.