How exactly do credits work

I signed up and I see that I need credits to unlock a page, how does this work? and is it possible to get them without paying??

Credits are a form of currency on this site that is awarded to users via posting threads and comments, receiving likes (iirc), or via releasing a leak that requires credits to be unlocked. Although yes, you can earn credits by contributing to Nulled via low quality posts (read here about low quality posts), you'll just get banned pretty quickly so I'd advise against doing that. Otherwise, credits should be very easy to obtain as long as you contribute properly to the forums.

You can buy them or just interact on threads you find interesting then use them to unlock threads