Sure, I can talk extensively about that - what are you most curious about?
I should also say, it's different for men vs women, because testosterone will thicken vocal chords and make the voice more masculine naturally, so trans men on HRT have an advantage this way, though trans men still often have to voice train, learning to pitch lower and trying to open the vocal tract more to have a larger, deeper voice both have to be learned.
(This all assumes puberty blockers were not provided and the transition is happening as an adult, which with the healthcare bans for minors in the U.S. is an unfortunately common reality.)
On the flip side, trans women don't see any improvement from estrogen to their voice - the vocal chords remain thickened, and their vocal tracts remain larger.
When I socially transitioned I tried to teach myself and voice train by myself, but after months of little progress, I decided to go to a local speech language pathologist (SLP). I continued to teach myself and train on my own, but the speech language pathologist was able to help direct me, and crucially, to demonstrate principles to help me learn.
I learned some of the basics of vocal training in general - how to sustain pitches and strengthen the voice, practicing SOVTEs, and other exercises singers or actors might do.
Voice training is grueling, one of the worst parts of transition. Vocal dysphoria is a nightmare, and in my experience even once my voice passed all the time (i.e. on the phone people hear a woman and I get "miss" and "ma'am", as well as in person), the voice still sounds wrong to me, and I can't hear it as a woman's voice. In that way it's similar to other kinds of dysphoria - I am much more sensitive, so even once I look like a woman to other people, I still see a man or boy in the mirror.
But with vocal dysphoria, you are constantly exposing yourself to your voice. With other forms of dysphoria, you can get breaks by not looking in the mirror, not having sex, and generally checking out of life - escapism and dissociation can be really effective, but vocal training demands regularly paying attention to your voice, and persistently altering it. It's psychological torture, and a lot of us struggle to make progress because of it. Some even use it as a form of self-harm.
It took 8 months of weekly visits to a SLP and daily, full-time training (i.e. every day I had exercises and I was intentional with my voice, and basically was voice training 24/7, always paying attention and changing my voice) before I saw a shift. The progress for me felt like a major shift all at once, a lot more of the work was cognitive than I expected, more about the ability for my mind to recognize what I'm supposed to be doing. In a way it felt like I suddenly just realized I always knew how to sound like a woman and it just clicked. The time it takes varies, generally voice training is a life-long effort and it never ends. My vocal dysphoria is some of the worst dysphoria I suffer on a daily basis, and some day it would be nice for me to train with the goal of helping alleviate my dysphoria, but up to now I have been more pragmatic and focused on having a voice that other people hear as natural and female. Here is a voice clip I uploaded 4 months ago - to me this voice reminds me of a gay man's voice, I can't hear a woman. :-/
Anyway, let me know what further details you might be interested in 😊