Imagine a place in the cosmos far from all gravitational and frictional influences. suppose that you visit that place (just suppose) and throw a rock. what will the rock do? why?

In a place free from all gravitational or frictional influences,
objects that you can handle follow Newton's laws of motion
perfectly.  We even see this in video from the International
Space Station, even though it's not free of all gravitational forces.

In such a place, if you were to throw a rock, then as soon as
the rock leaves your hand, it continues on, at the same speed
and in the same direction, forever.

Newton's second law of motion says simply that it takes force
to change the speed or direction of a moving object.  In a place
where there's no force on it, its speed and direction don't change.