Another operation is exponentiation.

That's what exponentiation does for you.

Step 3 How to connect the Phi function to modular exponentiation?

Logarithms are a simple idea, but I think they can get confusing because they're the inverse of exponentiation, which is sometimes itself, a confusing concept.

We have PEMDAS, and I'm going to write it this way just to make it clear that we do parentheses, then exponentiation, then multiplication and division are at the same level.

For this he turned to Euler's theorem, which is a relationship between Phi function and modular exponentiation as follows m to the power of Phi(n) is congruent to 1 mod n.