what they actually do through to be able to transition"
That would be 'Nothing at all.'
I'm a man and I can transition just by saying so. I don't need drugs or surgery and don't need to even shave or buy a dress. My word changes reality.
I can even swap between man/woman on different days of the week.
If you're thinking of GRCs those are rare and most don't bother.
As for drugs as others have pointed out you can get them sent from other countries and there's still a plan to hand out puberty blockers for 'trials'.