Newton's third law is: For every action, there is an equal and opposite reaction. So, some examples would include when you jump, your legs apply a force to the ground, and the ground applies and equal and opposite reaction force that propels you into the air. Another example used every day would be walking or running -- A person who is walking or running applies Newton's third law instinctively. For example, a runner pushes backward on the ground so that it pushes him forward.
Hope that helps :)
