Working out pre-T

Hello fellow men lol.

I really want some advice on working out pre-T, specifically growing muscles and becoming bigger in general. My current timeline is that I'll be on T at the end of this year (with some luck), but I don't want to sit on my ass while I'm waiting for that.

My frame is quite small, quite skinny except my thighs (168 cm, 58 kg). While I have been a competitive swimmer and runner, i.e great at cardio, I can't seem to build any muscles in my arms, shoulders and back. I mean, the muscles are there, just very lean, they don't show. Currently, I cycle and do intensive yoga to strenghten my core.

I have been to the gym this year to lift some weights, but I am a bit lost. What type of exercises are most effective, what weights or what equipment to use? Diet-wise, anything that genuinely works?

A lot of advice online is catered towards cis men and cis women, which makes me a bit dysphoric. So would love some help from the community here!

(I would preferably train in a way where I do a full body work-out without any equipment besides dumbbells. Let me know if that's even feasible.)