I'll add that algebra is the bedrock of ME, I'd recommend you starting at the beginning and going through all of these videos to brush up and get really solid on factoring, distributing, etc: https://www.khanacademy.org/math/algebra
Here's another course that's fundamental to ME: https://www.coursera.org/learn/mastering-statics
(Not trying to overload you, but it might be a good idea to try out some ME coursework to see if it's really what you want to do. There are a lot of other fascinating engineering disciplines you might happen to prefer, and the sooner you discover that, the better! Though ME might be right for you.)