I`ll say start learning all about the Major Scale.
That is:
Step Pattern.
Intervals
Positions
Arpeggios, etc.

I mean, there`s a lot you can learn.
Asking what you sould learn next is an open question (too open).
So, do your research on any topic you are interested in. And then ask more concrete questions.
Good thing is you have curiosity and hunger for musical knowledge, and you can get good advise here in the forums.

If I was to recommend a guitar, I`ll say: a guitar with 24 frets, and the brand and features are a matter of how much you can afford.