1>What changes i'll have to make and where in order to see the profile page?
From the Readme.txt file that comes with Community Builder:
8) Add a new user menu item for the comprofiler component
(this will be the users profile page).
For this, go to menu -> user menu, click New, select component,
then Community Builder (com_comprofiler), give a name and save.
9) Add a new user menu item as a Link-URL and point it to
index.php?option=com_comprofiler&task=usersList
(this will be the searchable users list).
For step 8 - Be sure to select Component as the Menu Type and then select the Community Builder component. This will give you a correct menu link to the profile page.
For step 9, make sure that you are creating a Link-URL type menu item and then give it the URL specified in step 9.
NOTE: You can modify the default user list and add additional lists which can vary in terms of who can access them as well as what information is displayed. It is quite flexible.