How do I give users access to multiple pages / levels?

Can't find an answer to this anywhere.

Basically, I want to give users specific access to a lot of different pages. For example, User1 needs access to Page A and Page B, User2 needs access to Page B and Page C, User3 needs Access to Page A and Page C.

If I have access levels like these:
Level A - Access To Page A
Level B - Access To Page B
Level C - Access To Page C
etc.
...and I assign User1 to Levels A and B, then they cancel each other out and they have access to nothing.

Is there a way of assigning levels like this, or would I need individual levels for each user that specify exactly what they can access?

I am starting to think I chose the wrong plugin and might need an alternative solution...