vague question.
"the best things that i need to buy".
now there's a never-ending question! no matter what you buy, there always will be something better (unless you have millions to dedicate to this).
start with a project, choose a room (that will be acoustically treated), plan on what you are going to record, how many inputs you need, what ouboards you might use, how many mics, how many miles of cable, build a dedicated pc or use a multitrack recorder, consider what monitors and if you need a sub, learn how to use and if you need a patchbay, start thinking about a mixing console... etc etc etc...
it's a loooooong road
