Well for both of them to survive they need oxygen, food, water amino acids, and a way to leave waste, but that depends on the type of cell
The molecules which store and process genetic information is DNA - deoxyribonucleic acid.
So white blood cell’s(WBCs for short) main job is to fight infections.
They do this by swallowing the infection.
You see,WBCs do not have a permanent shape.this means that they enlarge and decrease size of parts of their body.So they grow two long arm like structures called pseudopodia which swallow the infection.(pseudopodia means false feet).
You can see the process in the photo I attached from google