I have a question about how i can manipulate a 2d array without actually making the 2d array
I've got news for you. You can't manipulate something you didn't make.
The issue comes up with the fact that i cannot make a variable number of these objects
A variable number of what objects? Instances of the enter class?
Of course you can create a variable number of them. What you can't do, without using malloc() or new() is create a variable length array of them.