a team can call 20 second timeouts or 1 minute timeouts (full)
Yes, it is legal.
Yes, the assistant can call a timeout, players on the court can also call timeouts.
Coaches, players, and referees.
In an NBA game, each team is given six timeouts. They get four 60-second timeouts and two 20-second timeouts.
you get 6 timeouts in college
You get three 30 second timeouts and 2 full timeouts per game