You can pass data between pages either using sessions or cookies,
In the database you would need to have another column along with the username and password for the user level or status.
The simplest way to have user level restrictions would be to have tiers, for example, photographers are level 1, users are level 2, these would need to be sequential. And in the code check the users level field in the DB to see if they have permission to access the page. Level 1 would be able to get to anything for 1 and higher, level 2 for 2 and higher etc..
Have a look on Google, there are alot of articles on this subject. As well as sessions and cookies.