Wordpress tutorials or what is this type of site called?

Question

WordPress

Hey! There was a need to write a registration / login plugin + personal account.
After much torment in the basics of writing plugins in Wordpress, I figured it out, I also mastered and found articles on registration and login, but I don’t understand how to implement a personal account. This is a rather difficult thing, as I understand it, but I still thought there was some kind of tutorial on this.
I realized a long time ago that nothing like this could be found in Russian, so I decided to look in English. I came across the term membersip site, which seems to reflect the type of site that I need. But I dug up only tutorials where programming is not used at all, but I still would like to develop as a coder.
The request is this: If you know any series of lessons in any of the two languages ​​(Russian / English) on this type of site or know the correct name for such a site - write, I will be extremely grateful.
Thanks in advance!