Thanks very much @robkk. The link on wp user query is a great tool to solve my problem.
Concerning the use of BuddyPress, i think the link will be a problem in the sense that the links to the profiles that will be displayed will not link to the users forum profile. I want the links to go to user’s bbPress profile page, not the default wordpress user page nor the buddypress profile.
So I have decided to go by the Wp user query way, but please how am I going to create the php code. Am i supposed to wrote it in a page? or where should I put the code and how will i create the page?