Subshells of the atom?

Your text has been cruelly wrong. An orbital can record 2 electrons. However, the sub-shells have one to several orbital more accurate s=1, p=3, d=5, f=7 etc. They can therefore record electrons 2, 6, 10, 14 etc.

To explain what sub-shells are, you have to pick up something further. As you may know, electrons can also be described as vibrations or waves. These can swing in the ground tone, so to speak, then they have only one waver, or as an overtone, then there are nodes where nothing swings. It was best to perform with a string instrument, but it’s bad to go over the Internet.

The shell number is accordingly the number of regions with a uniform vibration direction, which is also referred to as a sign of the wave function. The number reduced by one thus results in the number of node surfaces at which the sign changes.

In the first shell you have only one area, so no node area. In the second shell you have a knot area. And, now it’s going to be exciting, that can be spherical shells, at the 2s orbital, or a plane duch the core, at the 2p electrons. The planes are perpendicular to one another in the 3 spatial planes, so there is px, py and pz. This means that an electron cannot be at the core from which it is attracted. Of course, this is energetically unfavourable.

I don’t know if you understood a word. Therefore, I only add the indication that d-orbitals 2 and f-orbitals have 3 levels through the core, which gradually makes them “unpopular”. They are therefore 1 or 2 periods later filled, 3d in the 4th period and 4f in the 6th period.