Surgery and transition
Transition is a term used to describe the process a person goes through when changing their gender, this can includes social changes such as changing appearance and name change and it can include medical interventions, but not always.
Despite what you read in the papers, not all trans people have surgery, sometimes this is because there is long waiting lists and healthcare services that are extremely difficult to navigate, sometimes it is because they don’t want to! It is not a requirement that a person undergo any surgery or medical process in order to change their gender.
For some trans people, gender-affirming surgery is essential to their health and well-being. If you are curious about an anatomy then google is your friend, don’t ask a person what they have in their pants, its rude!