The inbounder has 5 seconds to inbound the basketball once they are given the ball by the referee. If the inbounder is inbounding it from their baseline after the other team scored, the inbounder can run side to side along the out-of-bounds line.
The defensive player can move side to side and jump to block the inbound pass. However, they may not reach over the out-of-bounds line. If they do this and touch the ball, they can get a technical foul.