Question

write the maximum number of shells that they can be accomodate​

Answer 1

The M shell can actually hold up to 18 electrons as you move to higher atomic numbers. The maximum number of electrons you will find in any shell is 32.

Answer 2

Innermost orbital shell means 1s orbital. So it can accomodate maximum 2 electrons . Inner most orbital being S can accomodate 2 Electrons as per Pauli's Exclusion Principle. P can accomodate 6.