Hi Habib,
You can control internet access in may ways. If you have static IP address for internet access, then I would suggest adding and acl in inside of router R2.
In the below example, the acl internet_users will control internet access.
!
ip access-list extended internet_users
permit ip host 172.22.10.1 any
permit ip 172.22.15.16 0.0.0.7 any
!
interface fastethernet 0/1
description <<<<< Inside Network >>>>>
ip access-group internet_users in
!
If you are using dynamic IP address assignment and if you have Cisco Secure ACS, then use proxy authentication on Internet Router R2.
