How does entropy relate to osmosis and diffusion?

Hint: We need to remember that entropy is the concept introduced in the second law of thermodynamics. It is used to measure the randomness of a system. In spontaneous processes, the entropy of an isolated system is increased. In a non-spontaneous process, the entropy of an isolated system decreases. In the equilibrium process, the entropy of an isolated system becomes zero.

Complete step by step answer:
We must remember that the entropy is a process for things to spontaneously spread out and go from highly concentrated state to less concentrated state in diffusion. Heat energy goes from a high energy state that one is highly localized to a lower energy state that has a lower density of molecules.
We must know that the diffusion means one molecule is diffused to form more molecules. In this process randomness increases and entropy increases. The diffusion in the unstable molecule is spontaneous, hence the entropy is increased. Diffusion is one of the direct results of the second law of thermodynamics. In diffusion means, large molecules are spread out in all the directions lowering the concentration of the molecules in the original space. The entropy of the universe is becoming more diffuse than others.
We need to know that the Osmosis means the solvent molecules pass through a semipermeable membrane from a solution of lower concentration to a higher concentration solution. Osmosis is one of the diffusions that is controlled by a semipermeable membrane. This membrane allows diffusion in only one direction. Though large molecules cannot diffuse, only small molecules diffuse due to the size of the openings in the membrane.

Note:
We also remember that the entropy is measured in the system and surrounding. The sum of the entropy of the system and surrounding is equal to the entropy of the universe. Due to heat energy, the rate of expansion of the universe is increasing causing the universe to become lower in heat. The total entropy or heat energy of the universe is always constant but will become so diffused that there will be no usable matter or energy left.