Most educators receive little formal education about queerness, transness, and gender fluidity. Most students do not learn about gender and sexuality in K-12 schools outside of health lessons or anti-homophobia campaigns. Teacher education programs do not require that teachers learn about gender and sexuality. This means you have been systematically denied education about queerness and transness, so if you are worried that you do not know enough and will make mistakes, there is a chance this is true.
That being said, it’s okay if you don’t know everything! It’s okay if you are a novice. Would you get upset at a student for not understanding something they were never taught? Would you tell them to stop trying if they made a mistake? Making mistakes are part of learning, some mistakes can be more harmful than others and it is important to learn how to respond with care when we blunder. Learning about 2SLGBTQIA+ people is a literacy that requires practice.