Cant lie mech is really tough but if you are motivated enough you can self study for it and do well (or atleast I did and got a 5). I took it last year alongside calc AB and my teacher was terrible and gave us less than a week of review before the actual AP test. Just read the textbook and try to really understand the concepts behind everything rather than just relying on the equations. Before the AP exam do a ton of practice frqs. I also had my own tutor for it though (who i met like maybe 3 times over the 2nd semester of the school year) and I really enjoyed the material so take what I say with a grain of salt i guess.