Law / Permanent stay in Poland for a engaged brazilian? [9]

Dobry wieczór!

My name is Cesar, a 20 years old polish-brazilian from...Brazil :duh:
I'd like to know if it's possible for me to move there permanently for I intend to study and work as well.
If so, how difficult is it?
Well, I'm an English teacher and writer, so I'm basically fluent at the language (despite not being native).
Also, I'm studying Polish here where I live and know some things (well...really few things, haha) but I can say that is not enough to have a 'deep' conversation yet lol.

Honestly, I'm quite ashamed of having to come here (nothing against the forum, of course), you know...being immigrant(?) is not a cool thing for me. But as my grand-mother was a Pole, so...well.

I've applied for my citizenship but my great-grand-parents came here in 1912, thus the procedure is being quite tiresome and it seems it'll be impossible. (for me, the reason is just unfair, but anyway - this is not the matter here).

Just some another questions/observations:
I'm engaged - Is there a way to bring my fiancée with me? She speaks english and a bit of french as well

I'd like to live in Gdansk/Gdynia for I want to study at the University of Gdansk (Philology - Scandinavian studies); Is it possible for me to study there?; Is it a good university (cost-benefit)?

Is there a lot of muslims there? I mean...well, you know. Just feel a bit unsafe with muslims around as I read news on the internet (Don't mean any disrespect, anyway)

I apologise for posting a first prolix thread like that...I just like detailing things ;p and well, I'll be really glad if I get any answer and please, be nice ):

Dziękuję!