https://www.usembassy.gov/
https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/list-of-posts.html
So the more I investigate, the more I found conflicting information. Some suggest it's best to wait, some indicate K1 approved petitions just schedule their own interview. I went ahead and set everything up for my fiance and we're booked for February 24th. I was able to locate her approved medical exam location and convinced her to schedule it herself. Follow the links above to locate the embassy information for the country you need. If you look at the wording it's tricky. It says, in bold red, you must schedule your own medical exam WHEN you get your appointment date, three weeks ahead. Well, if you go to the embassy website and pay the appointment fee, you can get your appointment date, violà... You're moving on ... Book the medical
Surprisingly everything is going smooth for now, fingers crossed. She has all her documents now, her medical exam requires x8 photos. I sent her a fed ex package with the I 134, tax information, photos, extra copies of the appointment letter, copies of exam appointment, our approved NOA2 copy, fresh letter of intent to marry and some pictures of us on vacation for evidence.
My first responses of being patient, I was under the impression it wasn't possible to proceed unless I had the welcome letter but it seems it's possible if you're detailed, read everything and follow the steps.
You'll have to create an account on a third party website to pay and schedule the interview because it's now in their country and they need to get paid separate from USA. Register, use your email. I tried with my fiancé email and she never got the registration verification email. When I used mine, I go it asap. Pay the fee and schedule. Fiancé will need to bring the print page to her interview appointment for proof of payment. Fiance needs to brings ds160 and everything else to appointment. Use the links above, each country has different instructions. Best regards