Hi everyone, I'm a newbie here and for cars. I bought a 2012 Mazda 3 at 34000+, it had a minor accident on the front passenger side, it was fixed privately but when I drove it to the mazda dealership to have the fuel system changed, they discovered that the wheel bearing had to be replaced and most likely, it was damaged by the accident. I had it changed by another mechanic since the dealership was way more expensive( they won't cover it due to the overpaint found). Now, I haven't done any service to the car and have no idea how to change oil/ add water myself. The only thing I know how to do is to refill the wiper liquid.

My question to you guys here is if I should bring this car back to the dealership for service or I can use any private mechanic around my neighborhood? The car now has 36600 miles and the AC is not as cold as I wanted it to be. There's a dent also on the front passenger side, I think it was either hit by another car while it was parked on the street. The dent is quite noticeable but there's no paint coming off, should I get it fixed? And if so, what's the cost I have to expect?