You will not be able to eat or drink out of this type of ceramic piece.
Whether or not you can do handbuilding without a kiln depends on the type of clay you use. If you are working with a self-hardening clay, you can let it dry overnight instead of firing it. There are also kid-friendly polymer clays that you can bake in the oven. The downside of these types of clay is that uses of your ceramic piece will be limited. You will not be able to eat or drink out of this type of ceramic piece.