Because the teacher asked me to prepare my own courseware and then replace the teacher in teaching, a classmate planned to put an ugly photo of me on the courseware, just to make me look embarrassed.

You should not fight back and turn a blind eye to him. There is a saying that if you don’t blame others, you will be defeated. On the one hand, everyone will see you as a big person, with quality and measure. On the other hand, everyone will see him as a clown with a sinister and ugly heart. In short, if you mind and fight back, he will be happy. It will work. No matter how you fight back, everyone will laugh at the two of you. That means you fail or you two fail together. If you don't mind, it doesn't matter, he will find it boring. If he fails, everyone will laugh at him alone, will you elaborate? Do you understand?