Hello!
If you are talking about a plant cell wall, then plant cell walls are mainly made up of cellulose. Cellulose is a long fiber polymer containing hundreds of glucose molecules.
Meanwhile, animals do not have a cell wall, so their cell wall is not made up of anything. The cell wall provides structure, support, and protecting for the cell, but apparently, it is said that animal cells do not have cell walls, meaning they do need the structure, support, and protection from the cell wall.
Hope this helps, have an awesome day/night! :)