Question

A cell requires water Minerals and other substances to work normally but the cell is covered with a cell membrane how is it possible

Answer 1

The cell membrane is selectively permeable I.e. it allows certain materials to pass through it. Water enters cell through osmosis I.e. water or fluid moves from high pressure to low pressure. Other materials move in or out through integral protein and some move with help of carrier proteins.
Hope this helps

Answer 2

Animal and plant cell differ in their outer layer. In case of animal the membrane which protect the inner contents of the cell is called cell membrane and in plant cell its cell wall. Here we will specifically talk about animal cell. The plasma membrane in animals not only act as a protective layer but it also controls the flow of water, nutrients and minerals. As plasma membrane is porous so it lets some substances to pass through it. In this way it keeps the cell strong and healthy.