Does anybody know a program where I can do voices for my game and works with Blender?
Depends on your O/S, and what you mean by “do voices”. A really good sound editing program is Audacity, which has the advantage of being open source.
This may be out of your range, but Sayz Me is a free Windows-running text-to-speech program that is written in Python. Maybe it can work with Blender, but it’d be pretty complicated.