A food festival is like a big party where lots of different foods from all over the place come together in one place. Imagine going to a playground where there are lots of different swings and slides to try out, but instead of swings and slides, there are booths with all kinds of food.
There might be a tent that sells hot dogs and hamburgers, and another one that has pizza slices. There could be a stand with pretzels shaped like animals or vegetables, and a booth that specializes in ice cream or cotton candy. You can try all the different foods and see which ones you like the best.
There might be some special foods from different countries, like sushi or dumplings from Japan, tacos or burritos from Mexico, or even some really different foods you've never heard of before.
It's really fun because you can walk around and see all the different colors and smells of the food, and choose whatever looks the best to you. Plus, you get to try lots of different foods and see if you find any new favorites.