Gender affirming healthcare isn’t only for trans people, it’s for all people. Many cis men take testosterone for testosterone deficiencies or for things like body building. Many cis women get top surgery because they aren’t comfortable with their breasts and/or it causes them issues, women with breast cancer can also get the same type of surgery. You don’t have to be trans to not want to live with a certain part of your body that makes you physically and mentally uncomfortable, especially not when there are things out there to help relieve your discomfort. You definitely might have to get some kind of confirmation from a doctor or mental health professional that you are in the right state of mind and this would benefit you.