If you try affiliate marketing in Google Ads without a landing page, the account will get suspended and if appealed, then finally suspended.
As usual, ineffective comprehension skills. See below :-As usual with generic wrong advice.
OP has specifically asked about "How to promote products on Clickbank with Google Ads" and Clickbank is specifically about affiliate marketing and affiliate marketing only. So, do not put a restaurant business into this scene.If OP advertises a restaurant they do not need a landing page.
You firstly rectify your comprehension skills and then reply to others.Ask for their niche first, then provide advice.