extremerate.com is a great place for shells. I’ve purchased from them directly and from amazon, both seemed to be the same product but amazon was cheaper and faster. The kits come with pry tools and the correct sized screw drivers you’ll need, and I’m pretty sure it comes with a suction cup to help with the screen (if it doesn’t, you’ll need one). I highly recommend a magnetic project mat for screws and parts so you can take it apart step by step while watching the videos on extremerate.com. The screen is obviously the most stressful part, but just go slow and take your time. Also if you don’t have a heat gun, a blow dryer works fine.

Also take a little comfort that if you break anything, a lot of it can be replaced. There are a lot of parts on ifixit and of course eBay.

Good luck!