I was doing my tax return and I just checked that the W-2 form that got filled out was the normal 1040, not the Non Resident one, what can I do to change that?

Are you a non-resident alien?

If you are a non-resident alien, your return must be filed on Form 1040NR, which cannot be prepared using TurboTax.  You can use TT’s partner, sprintax:

https://www.sprintax.com/non-resident-alien-tax-1040nr-turbotax.html

Yeah, I am 
I was helping out a friend with it, when I realised I had the wrong W-2 form. 
But, if I finished my tax return with TurboTax, would it be a problem if I do it again with SprinTax to correct that issue? 

If you haven't actually Efiled it yet, you can re-do your return with Sprintax.

@dgonzalezfernan 

Wait---what?   Are you the one who is a non-resident alien----and did you already e-file a tax return ----but you used the wrong W-2?   Was your e-file accepted?

Yeah, I think I've Efile'd it :( 
My return has been approved and I literally just checked that mistake an hour ago, can I change that using spintax? 

Yeah, it was accepted! 
It's literally saying that it's just waiting the IRS return

At this point I would advise you to do nothing and wait for a letter from the IRS.  You aren't the first person to ever file a return using the wrong forms and you filed so they won't be mad about that.  They will tell you what you need to do - if anything - to correct the issue with your tax return.

@dgonzalezfernan