I do remember we spoke previously about how you were with your dad iirc and he allowed you to buy girls' underwear. I was impressed at that. How do you think they will react if you tell them about transgender?

Please: even if they react badly, do not harm yourself. Sometimes it takes parents a while to get used to something. Please give them time and also ask them for the chance to speak to a therapist who is knowledgeable about transgender. That person could help you navigate the change.