A coordinator reads it against the partner centres' actual availability for your dates, then replies with a named program at a named centre and a fixed price. No account was created, and nothing has been charged.
The reply names which partner centre would perform the screening and which of its published programs yours is, so the price can be checked against that centre's own page rather than taken on trust. The four partner centres each publish their own document.
A quoted price is held for 60 days and charged on arrival in Seoul, not before. If the dates you gave cannot be matched to a slot, the reply says so and offers what is actually available rather than quietly moving you.
Do not book the hotel yet. Which centre performs your program is settled with the program, and the four sit in different parts of Seoul. A room five minutes from one is forty minutes from another. The accommodation notes list the districts and what is near each.
Check the entry rule for your passport, if you have not. For most nationalities a screening trip needs no visa at all. The entry check answers it in about a minute, and if yours is a case that does need one, say so in your reply and it can be handled.
