Oh, tough question. Math is the most complicated discipline for me; if I don't have a formula, I cannot solve something. And it's a problem for me because I have math twice a week, and I have to do homework, and there are a lot of tasks to do. I have a tutor, and she helps me to understand everything better, and I also use this site
https://plainmath.net/secondary when I need help with solving. There I can find similar tasks and see how everything was solved, or post my own question and get step-by-step solving help. It's a great helper for students, and some guys from my group also use that.