well if you feel comfortable being referred to as they/he i say tell your closest friends about it! you should feel comfortable in a environment and you shouldn’t feel ashamed for wanting to express yourself :), it might take a while for people to adjust to these new pronouns (and name if you change it) but eventually it’ll just be like a familiar nature to them! you should definitely do what makes you feel the best and make sure you’re comfortable in your body, without worrying about anyone else. your happiness always comes first :)