This is a “put yourself in its place” question. There is no single right answer. Think about what would be fun and what would be hard, and say both.
Sample answer: Living like a frog would feel free and a little frightening at the same time. The best part would be having two homes. When the day is hot I could slip into the cool pond, and when I wanted to look around I could climb out on to a rock. I would never have to wait for a bus, because my back legs would carry me a long way in one leap. Rain would be the happiest weather of all, not a reason to run indoors.
But it would also be hard. My skin would always have to stay damp, so I could never go far from water. I would have to keep very still and watch all the time, because a snake could be near. And I would have to catch every meal myself with my tongue — there would be no one to cook for me. I think I would enjoy the swimming and the leaping most, and I would find the waiting and the watching the hardest.