How should I tell my classmates/parents that I want to change my English name?

So basically I live in China where it’s normal for kids to have two names, a Chinese name and an English name. At school I do not have an English name, well, at least a feminine English name, thus everyone refers to me by my deadname which is super feminine. Deep inside however, I’ve always known that it is wrong. I am more comfortable with a male name, but I did not give myself an English name because I was afraid people would make fun of me.
The masculine name I chose for myself is Theophilus, or Theo for short. When I found out the name Theo is actually gender-neutral since it may also be a form of Theodora I was wondering perhaps it is possible for me to use the English name Theo at school. Nevertheless I am (almost) not at all, so I don’t how people will react to me changing my name as there is already a few rumours about me being a lesbian or etc. And I have no idea how my parents would respond to that, especially my mother, because she’s not so supportive of the lgbt community, although she has some level of acceptance of me being a lesbian(if I were one). I tried to came out to her once and she was like ‘no, you’re not (transgender), you are just indoctrinated by those social media.’
Any advice? I just don’t want people to make a fuss about my gender identity or make rumours about me being transgender(even though it’s true).

 

If that's the case then I guess it's better not to name myself Theodora, but keep using my deadname, at least for now. In some ways, it creates more deadnames, which I do not want. I only want to change my name to Theo because it's (sort of) gender neutral, so people will not think 'Ah, this person changed his name to a masculine one since he's a ftm transgender person!' or amything similar. But thanks for your help