Removing body parts that cause distress to a person is normal medical practice. If your appendix is causing you harm, what do they do? Remove it. If your tonsils are causing you harm, they remove them.
For people with gender dysphoria, certain body parts will cause them psychological harm. Removal or modification of those parts has been shown to provide significant, marked relief for patients who opt for those procedures.
"Self harm" refers to a mutilating practice that serves no functional purpose. There is a functional practice to gender-affirming surgeries. Quit trying to make up your own definitions for words and phrases and pretending that your version is reality. Literally thousands of professionals in this field disagree wholeheartedly with your uneducated, uninformed, baseless assessment.
Read a fucking book. But not My Shadow Is Purple; that seems to be a bit too advanced for you just yet. Have you heard of The Very Hungry Caterpillar? That might be a good starting point.
EDIT: Wait, no, I forgot the main character in that book transitions into a butterfly. I'll ship you a copy of Goodnight Moon, maybe.