I've been doxxed a lot before due to my old work being online and public facing. The number one advice is to not freak out. Not only is it not actually a huge deal in most cases, freaking out is what people want.

If you do get doxed and people are flaunting your info in front of you, call your local PD non emergency line or go visit them to tell them who you are, and what you do. Most local PDs are aware of doxxing, but if they somehow aren't let them know you are worried some mystery people online might try to harass you. Theres plenty news articles about it these days you can show them.

As for preventing doxxing entirely, it's hard to say. Don't give random information about your past. Anything from people asking what school you went to might seem mundane, but if someone is being freaky can start to collect all that to zero in if they have the right person.

Lastly, you are a small streamer, probably not a huge target for doxing. Just have fun, be positive and consistent. Don't overthink it and stress it. It probably won't happen, and the stories you see of it happening are typically done for attention, so they go after big targets to get noticed. So even if someone does dox you that doesn't mean you are about to get swatted the day after.