Dad has been forcing me to practice my handwriting. What should I do?

Your father was right. Listen to your father. You don't like calligraphy now because you don't know the charm of calligraphy. It can not only make you write well, but more importantly, it can make you understand China traditional culture more easily by learning calligraphy. Your father doesn't force you to learn calligraphy now. When you really understand the importance of learning calligraphy, it will be too late. Finally, your great love for your father forced you to learn calligraphy!