Push it. Have your bartender offer it. Have the offer up in their face all the time. Pay your servers a bonus for selling food. Have specials on a chalkboard or similar where people see them all the time. Have menu's lying around - you should not have to open the menu to read it. Offer things people like with whatever sort of drinks are popular. Have good prices. You don't need to make a mint on the food. Sell foods that make people thirsty. Coincidentally, these tend to be the foods people like to order when they drink. Get a deep fryer if you don't have one. If you do, you're in tall cotton. What person with a few drinks in their belly can say no to fried food? They may not ask for it, but if you offer and make it visible...
There are tons of fully cooked, heat and serve foods available that taste great and require no skill to prepare properly. Talk to your distributor and local food brokers. They can give you tons of ideas and lots of samples of things to try. You want things that can be stored in a freezed and prepared from the frozen state. Then you have little worry about spoilage and can offer more options. Don't print expensive menus. You can run them on your computer daily. That way you can change them based on what you have and what is working for you. Run lots of specials and try lots of new things. Keep the ones that sell well and dump the dogs. Have some local favorites and some things they can't get other places.
I'd have lots of options finger foods and some larger items like hamburgers (go precooked), pizza, etc. Labor is your biggest challenge, so think simple, easy, foolproof, little labor.