i’m considering starting hrt but i don’t know what to do

as post title says

i’m wanting to start hrt, but i don’t really know what to do, i live in the uk and im 16 and closeted amongst family so its a bit of a struggle to book an appointment when my mum is not exactly the most aprotchable/ supportive when it comes to trans people

i’ve socially transitioned amongst friends and have been for like 2 and a half years now, but i’m just fed up with looking in the mirror and not seeing me