Now lets she s-subshell structure .
Take an element Berylium
[tex]\huge{\overset{1s^2}{\boxed{\uparrow\downarrow}}\overset{2s^2}{\boxed{\uparrow\downarrow}}}[/tex]
You can see the S-orbital has only space for 2electrons .
Come to p-orbital
Take an element Neon
[tex]\huge{\overset{1s^2}{\boxed{\uparrow\downarrow}}\overset{2s^2}{\boxed{\uparrow\downarrow}}\overset{2p^6}{\boxed{\uparrow\downarrow}\boxed{\uparrow\downarrow}\boxed{\uparrow\downarrow} }}[/tex]
The 2 means its L shell .
It has 8 electrons only and full filled .