When someone surrenders, they give up and stop fighting or resisting.
Surrendering can be a good thing, like when it stops a fight, or a bad thing, like when it means giving up on something important.
Examples:
He surrenders and puts his hands up.
The army surrenders to the enemy.
She surrenders her sword and walks away.
The cat surrenders and lets the dog win the game.
The superhero surrenders to the bad guy to save the city.
The robot surrenders and stops moving.