Been trying to create mock website of a sort, but can't seem to determine which page and page type is required in order for any new user to create a username and password, email etc...
Is it a feasible task on Apex? Or do i need to go to another program such as php?
Oracle Apex makes sense if you're storing those information into a database.
The simplest option to do that - if it is you who will be doing it for all users - would be a report with form on table. Wizard creates an interactive report (which is used to view data, lets you navigate to details and update/delete those information) or create new users. The form does exactly that: updates/deletes & creates new rows.
If you'd let everyone do it for themselves, then it is a form on a table.
When you click the "Create page" button, follow the Wizard which will create everything for you. Maybe it won't look perfect, but it'll work. Then you can make it fancy.