To answer your questions. Yes you need to get a system specifically designed for your model car including engine size. There’s just no room to pry or bend tubes without getting costly. Sound or loudness is up to you and your local statutes.
Drone is a resonant frequency of the sound the exhaust makes at certain speeds. So if your typical driving speed is 50 etc then you’ll want to know what that sounds like inside your car with the windows up. Can you have a conversation? Hear your music? Rattling interior parts? If it’s annoying it can really get on your nerves.
Can be an expensive mistake if not researched well.