Ah ok fair enough. Personally I would prefer "proper" DIY over contraceptives. I might be wrong but I think they use synthetic estrogen which is a bit riskier.
As for GenderGP, a quick overview of how they work (plus costs). You have an initial appointment basically to diagnose you over Skype or phone call, I can remember exactly, but this was ~£200, then you have monthly fees of £30, and they prescribe HRT which you then have to pay for (cost depending on what they prescribe, but approx £60 every 3 months ish). The only annoying bit is blood tests, which your NHS gp can do or you can have done privately (more £££). Note that I've heard some of the costs being reduced if you're low/no income.
If money is really right, then DIY is similar, but avoids the initial fees and monthly fee. But most people encourage you doing blood tests to keep it safe anyway.
Good luck! Feel free to reach out if you're struggling with family - I did a similar thing telling them when I left for uni.