Congrats! You passed the interviews, you got an offer and you have put your 2 weeks notice. So now you have a month or so before you start at the new place!
Do you prepare at all for it? If so what/how would you prepare?
the best way to prepare is to decompress and relax. There will most likely be a lot of new learning in the first six months at the company so you don't want to get burned out.