These lines on the outside of the last line holding the red dots are the outer shells. The red dots are electrons, which have a positive charge. The outermost shell holds valence electrons, which do bonding.
(Not paying attention) Hey what is the yellow thing?
The most inner shell holding two red dots( electrons) can only hold two electrons while every shell it goes up, it multiples by 4. For example, it goes from 2, to 8, to 32, and so on.