If your reception is going to be in a venue that provides food e.g. a hotel or restaurant, all you will need to do is select a meal to serve your guests from a predetermined menu. You can also customize your own menu should you want to. Incase your reception is going to be in a venue that does not provide food, you will need to hire an outside caterer who will be responsible for preparing, cooking, and serving the food and cleaning up after the event.
The caterer can also be responsible for beverages but this is entirely up to you. Book your caterer in advance especially if your wedding is going to be in the busy season. Ask to see the caterers portfolio including pictures of previous work so that you see how the caterer presents their work, ask for references and be sure to counter check on them or better still visit an event they are catering. Make sure your caterer is fully self-supported with catering equipment. A competent caterer will prepare much of the food in his/her own kitchen and should provide an adequate staff of cooks, servers and bartenders.
Before signing a contract, make sure you are clear on all the services the caterer will provide. Your contract should clearly state the amount and type of food and beverages that will be served, the way in which they will be served, the number of servers who will be available, the cost per item or person, and the rental items the caterer will provide such as tables, chairs and tableware.