In a situation the contact force by a rough horizontal surface on a body placed on it has constant magnitude. If the angle between this force and the vertical is decreased, the frictional force between the surface and the body will
decrease
Now if the angle made by Fc and the vertical decreases then horizontal componenet decreases
As you can see the horizontal component decreases, Which in this case turns out to be frictional force.
Yes the magnitude of frictional force depends upon the angle made by Contact force and the Vertical/Horizontal