How do you open it?
1) Suction cup.
2) Screwdriver kit that contains pentalobe and torx bits. You don't need to buy some expensive kit as you can get them cheaply from any hardware store.
I think Apple finally won with making their computers impossible to open.
TLDR: Remove the screws on the bottom. You need a special screwdriver and keep in mind that (at least on the <=2015 models afaik) there are different size screws used around the hinge.
I've used mine to take apart every conceivable consumer electronic, and through social bits for Nintendo, Apple, etc are priceless.
I also got the magnetic mat, a Christmas gift from my wife, and when disassembling things with lots of screws is useful for drawing out the device for their location.
P5 Pentalobe screwdriver: https://en.wikipedia.org/wiki/Pentalobe_security_screw