1. Can I make another Module to this same workbook, and make this new userform only to use the another Module? I mean is it possible to make one userform to use only one module? If so, How can I "link" them together?

2. Or is it possible to make a macro which changes the template what is going to be used?
If I understand the question correctly, you are concerned about a UserForm using the wrong code.

You should not have any problems if you follow and understand a few simple rules:
a. All the bulit in UserForm routines are automatically Private. That means they can only be seen by that specific UsrForm.
b. In general, my personal design guidelines are to make other routines inside the UserForm code module also Private. I try to have as little code inside the UserForm module as possible.
c. I usually make routines in other modules 'Public' (accessible to anyone). To avoid a conflict between two Public routines, requires careful use of Routine Names.

For example instead of a function called UserFormVerifyData(), if I would name the routine(s) UserForm1VerifyData(), UserForm2VerifyData() etc.

I hope this helps.

Lewis