How to generate url for user?

Question

Web development

Tell me where to dig or is there a ready-made example, maybe?

I am making a registration system, I can generate user profiles, but in this format, for example: site.ru/profile?id=1

I want to do it differently and I don’t understand how to do it yet.

Let's say my user has an alias "admin" which is stored in the database.
How can I make a profile url in this format: site.ru/admin

I don't quite understand...