Best stoichiometry/math/unit conversion resource or videos?

My number one struggle with c/p is that I understand the concepts pretty well but once math gets involved my mind just shuts off and I become extremely prone to making dumb errors (such as exponents being off by 1 unit or messing up fractions).

Even on the actual mcat I had a massive brain fart on a simple unit conversion question and spent like 5 minutes on it (and I probably missed it too). C/P scores have been between 125-128 on FLs, massively hindered by math skills

I’ve never been good at math (failed calculus x2) but I need to improve