Hi bluejeans, will your guests be able to sit down to eat ie use knife & fork? If not, then you need food which can be eaten with just a fork, else finger food.
Then decide whether you are going to do hot food or cold food, or a mixture of both. What kind of food would you like to serve? What's the occasion (partly being nosey but partly to find out how formal/informal it is)
Sometimes, I think hot can be simpler cos you make, say, a chilli, a chicken curry, a beef or lamb casserole, something vegetarian (or less meat more veggie depending on your guests). Make ahead, reheat in the evening, serve with rice, couscous, potatoes, big salad and that's the savoury bit done.
Or you can do lots of different cold dishes (chicken salad, quiche, etc etc & salads).
You could theme it (e.g. Mexican or Italian or Greek)
Depends what you want... any thoughts.
(Desserts less of an issue - focus on getting your mains sorted).
Re drinks, do you know what the drinks preferences of each guest is (i.e. I almost always drink wine at a party, DH beer - do you have any idea? If not, no matter!)