A good way to understand how it’s used is look at the default content & default template...
1) You have to insert the
WebLogin snippet in your template, where you want a login box displayed. You have to set a few parameters : the page where you want the user to land after login, the page where you want the user to land after logout and the template chunk you want to use if not using default... for the other options check the bundled documentation of the snippet.
Sample :
[!WebLogin? &loginhomeid=`36` &logouthomeid=`0` &tpl=`FormLogin`!]
2) You have to go to
Users > Web permissions, then create user groups and document groups, and then associate users groups to documents groups to control access.
You should be set !