There are many people who do not think there is a hand technique in Taekwondo.
However, if you check the Poomsae or Taekwondo textbooks, you can find a lot of hand techniques as well as foot techniques.
You can learn the skills of attacking and defending with dozens of parts of the upper body, as well as hands and arms. The whole upper body is weaponized by the method of initial power which maximizes the power for each part. This allows you to perform attack & defense techniques in response to various situations.