For HRT, most of the US is under informed consent, meaning you can sort of just schedule an appointment, they tell you the effects you can expect, and then if you're comfortable with them you get a prescription that appointment. The most common place to go for that is probably planned parenthood, but if that's not super accessible there are some telehealth ones like folx and plume you can also use. I personally started with folx and ended up getting an appointment within like 2 weeks of making up my mind about starting, and picked up my prescription the next day (though they can also send you hrt through the mail if needed which is nice). Without insurance you'll be paying out of pocket, the cost of which varies based on medication and supplier. The type of hrt that's cheapest out of pocket is probably oral, but that might also depend on where you get it from.

DIY is also an option, since that cuts out a decent chunk of the cost (and has other upsides like less medical gatekeeping and risk of being underdosed). For that I'd look at the diy hrt wiki, it has more info than I do (in general this is worth checking out honestly, it has a lot of good info even if you don't end up doing diy). For DIY I do think its easiest to start by trying mono-therapy though (eg just estradiol), that way there's less to worry about with things like potential complications from whatever anti-androgens. Injections are also probably the cheapest option when doing diy.

Sorry for the wall of text lol. Just wanted to make sure I covered enough info to be useful. And feel free to reach out if you have any questions, either directly or to the community at large!