Is giving money to an employee responsible for maintenance work in a school, after submitting a bid lower than competitors, considered a bribe, knowing that the one who paid the money did not add it to the bid, and that the employee stipulated it for the work to be awarded to him, and is that considered an urgent necessity for the work to continue?

What you paid to the employee is a bribe and an embezzlement. It is neither permissible to pay it nor to take it, as the employee performs his work for which he receives a salary. A gift to an employee is a bribe, as the Prophet, peace and blessings be upon him, said: "Gifts to officials are embezzlement." And the Messenger of Allah, peace and blessings be upon him, cursed the briber, the bribed, and the intermediary. You must seek forgiveness and repent, and not return to such acts, for the paths of lawful earnings are many.