Adwords can be very powerful, however, when selling food/delivery - please use caution with this type of advertising. When you start a campaign you need to watch your spend like a hawk so that you don’t wind up paying $20 to sell a $15 pizza.
For example, if you are willing to pay $0.50 per click, and you receive 100 clicks, you just spent $50. If none of these clicks convert into an actual sale, you wasted $50. If only one click converts into a sale, you just paid $50 for one new customer, etc, etc…
2 Things to Understand (For Beginners)
Impressions = Number of times your ad displays on the screen (to a customer)
Click Through Rate (CTR) = Number of times your specific ad is clicked on by a potential customer
Conversions = Sales
I would highly recommend that you avoid using PPC/Adwords altogether unless you have an excellent “landing page” + online ordering. If you do not have both of these, your “click” will only cost you money and result in a very limited number of conversions (sales).
Please let me know if you have any question, hope this helps!