When someone sends something, they cause it to go or be taken to a place, especially by mail or email.
Sending something is usually a helpful or kind thing to do.
Examples:
She sends a letter to her friend.
He sends an email to his boss.
The teacher sends a message to the parents.
The bird sends a message to its friend in the sky.
He sends a big present to his sister.
The queen sends a letter to the king.