For food regulations you would need to talk to whoever manages food regulations in your country/area @Marina2065
Yes if hosts think this is a good idea they can promote your business to their guests.
You can give the host promotional flyers with a code for their guests to quote so you can pay a commission to hosts for promoting your business.
Personally my guests just use local food deliveries or one of 30 cafes and restaurants within a five minute walk of my house or the thousands of cafes and restaurants in our city centre less than a mile away.