yes he can. as a goalkeeper you dont give up on goal never ever!
yes he/she can for example if the goalkeeper is going to kick the ball and puts it down he/she can pick it up and move it somewhere else.
Only inside the box.
Only if it was thrown-in by the opponents, not from a team-mate.
It depends on how the goalkeeper received it. If the goalkeeper received it from a deliberate kick or a throw-in by a team-mate, then no. Otherwise, yes.
Yes it can be done, as it is not a back pass.
A goal keeper may pick up a ball directly from a throw-in by an opponent.A goal keeper may not pick up a ball directly from a throw-in by a teammate. This is one of the Indirect Free Kick infractions.
If a defender passes the ball back to his own goalkeeper using his feet then the keeper cannot pick it up, he can only use his feet to clear or pass the ball. however if the defender passes the ball back to his keeper using another part of his body (excluding arms and hands) then the goalkeeper can pick it up.
Yes. If the ball is kicked to them or thrown-in to them directly from a team-mate. If the goal keeper releases the ball from their hands they cannot pick it back up again until another player touches it.
No, a keeper may not pick the ball up on a pass back. If they do so, an indirect free kick is awarded to the opposing team.
if it was not a pass back then he's allowed
It is when the ball carrier drops the ball. Eventually, the other team will try to pick it up because it gives them possession of the ball.
No, the only place a goalkeeper may handle the ball is in his own penalty area.