Im in need to set custom permalinks to a post category. WP theme doesnt allow the URL as i could want it and i was guessing if there is a function to set a permalink of a page as follows:

www.mydomain.com/categoryiwant1/categoryiwant2/postname

But doing it by code, by wp codex like getting the id of the post and then setting the permalink by a function.

Could you assist me with that?

Thank you in advance