pls explain why does a astronuat feels weghtlessness in a space shuttle in orbit of the earth????? Also explain the relation between weightlesnss and free fall

An astronaut feels weightlessness in a space shuttle in orbit of the earth because a person feels weight only when the surface on which he is standing exerts a reactionary force on him.Since the acceleration of the astronaut and that of the satellite revolving around the earth are equal( each equal to acceleration of earth), the acceleration of the astronaut with respect to satellite is zero. Therefore person is weightless with respect to the satellite.

Weightlessness is absence of reaction force exerted by the surface on which we are standing.

Free fall is falling from a certain height with the acceleration due to gravity, that is 9.8 m/s^2.