Re: Multiple access points for tiki users (in my site )
First of all, Welcome Kyu to Tikiwiki COmmunity! 
and yes, it's possible. You can set object permissions for group A of users different than those for group B of users.
You can also use different homepage for users in each group so that they are redirected automatically to their own when they login.
And if you are using Tiki4, when you master this, and only then, I suggest you to play with category permissions. If using Tiki3, you can also have a look at them at early stages.
The permission system in Tiki is very powerful, but requires sometime for new users to get used to it.
Read the documentation with care, since it might not be updated to current Tiki versions on things related to category permissions, at least.
HTH
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