How many orbitals are there in the seventh shell?

Hint: The orbitals are formed only when they possess the same value of principal quantum number. The number of orbitals present inside the shell is square of the principal quantum number which is given as ${n^2}$.

Complete step by step answer:
There are three quantum numbers which help to determine the orbital where the electrons are present. The three quantum numbers are Principal quantum number, Azimuthal quantum number and magnetic quantum number. The principal quantum number is denoted by n which describes the size of the orbital. The angular quantum number or the azimuthal quantum number is denoted by l which describes the shape of the orbital. The magnetic quantum number is denoted by m which describes the orientation of the space of the particular orbital.
The orbitals which have the same value of principal quantum number (n) generate a shell. The orbitals which are present inside the shell are divided into subshells and possess the same value of angular quantum numbers.
The number of orbitals present in the shell is the square of the principal quantum number which is given as shown below.
${n^2}$
For example: The orbitals present in the second shell are given as shown below.
$\Rightarrow {(2)^2}$
$\Rightarrow 4$
In the question, we have asked for the number of orbitals present in the seventh shell, so the number of orbitals is given as shown below.
$\Rightarrow {(7)^2}$
$\Rightarrow 49$
Therefore, the total number of orbitals present in the seventh shell is 49.

Note:
The maximum electron an orbital can hold is two and both the electron should have the opposite. In the seventh shell 49 orbitals are present so total electrons present in 49 orbital is 98.