Can anyone suggest how to do this?

Hi all,

I need a membership site with the following capability

1) I would like my users to compile their profile (after name, email etc) by selecting categories and dependent tags from a dropdown. If the cannot find what they need they can add their own category and dependent tags which are then added to the database. Admin is informed when tags are added and the relevant user base is also informed.

(2) Users can search for other other users who share common tags by simply hitting “search”. The platform uses their tag profile as the search criteria and returns a list of users arranged by strength of match.

If any one could make suggestions how to this I would be very grateful.