I don’t really like it when registration requires a bunch of steps: documents, confirmations, SMS codes. That's why I was pleasantly surprised when everything went in a couple of minutes on https://pari-mobile.com/. I just entered the number and came up with a password - and that's it, you can use it. This is important for beginners, so as not to scare them off with complications. If you want a simple start without unnecessary things - I personally recommend this site. It works stably, and you don't need to bother.