Teen shaving

Okay so I just turned 13 and everything is fine in the period thing but idk about shaving lol

I know how to do it down there but I have questions about legs and arms and stuff and I’m in need of tips, my mom passed when I was 9 so I’m spending puberty and being a teen without a mom figure and I don’t have a big sister that can teach me this stuff so my questions are

How often do I shave?

Do I shave my arms too? (Im latina, my skin tone is passing but i have thick black hair and its not like that doesn’t show on my arms lol)

I have razors but do I like just do it while showering and like with just water or do i soap myself up and then shave or? Like idk any if this so anything that y’all can tell me is helpful 🙏🏻✌🏻