Spectators, friends and advice from the side
Under FIP rules only an accredited coach may give advice during a match, in team and double-pair events and only during rest times. Spectators have no part in calls, and anything that comes onto the court from outside means the point is replayed.
Advice from the side
In FIP competitions, advice and instructions during a match may only come from an accredited coach, in team and double-pair events, and only during rest times. Friends calling out tactics from behind the glass are not covered by that.
Calls belong on court
The rules give no part in decisions to anyone watching. In a friendly game the four players make the calls between themselves.
Things coming onto the court
If anything that is not part of the game comes onto the court during a point, such as a ball, a bag or a person, the point is replayed.
Respect both ways
Players must be polite to everyone at an event, spectators included, and abuse aimed at spectators is treated very seriously.
Questions
Can spectators give advice in padel?
Not under FIP rules. Only an accredited coach may advise, in team and double-pair events, during rest times.
Can a spectator call a ball out in padel?
No. The rules give spectators no part in decisions; the umpire or, in a friendly game, the players decide.