How to create reflection and detect when ui objects touch and where they intersect [Swift]

I am trying to create a ping-pong game. I have already set up most of the logic (game start, game information, quit option, working paddles, and scorekeeper) and I am stuck on the main game functions (ball reflection off of the walls and paddles, and ball rotation in the direction of its movement).

If anyone chooses to respond to my question with an answer, don't spoil my practice with a full-fledged ping-pong game already programmed. I am only doing this for practice.

Thank you for your answers.