Question

How many orbitals can there be in an energy level?

Answer 1

The easiest way to determine how many orbitals an energy level can hold is to use that respective energy level's electron capacity, i.e. the maximum number of electrons it can hold.

If you know the maximum number of electrons an energy level can hold, you can use the fact that each individual orbital can hold no more than 2 electrons to determine how many orbitals you have.

The formula for electron capacity looks like this

max number of electrons" = 2n^2