Hi,
yes you can use "multiple IPs" for anything you like with a cisco router. E.g. map them to internal servers, use some for browsing some for VPN, etc.
Only, the learning curve with cisco is very steep, make sure you can resort to a competent person in case of problems.
It is not recommended that a beginner tries anything more than a very basic configuration with cisco products. The consequence is usually an huge loss of time and frustration.
Hope this helps, please rate post if it does!