There is only one reliable way to do market research, and that is to sell the product. Find a restaurant with an outdated website. Go into the restaurant and take a paper menu and create a website with the updated menu, make the website responsive, if you can't upload the information to Yelp, screenshot the Yelp page and replace the prices and photos with Microsoft Paint.

Walk into the restaurant and sell it to the owner. If he buys it, congratulations! Now you have to go build it.