Tailwind Airlines Check-In Confusion: Online or Airport? Can I Bring Medication for Flight Anxiety?

Hi everyone, I booked a tour to Egypt and I'm confused about the check-in process for Tailwind Airlines. The airline says that check-in should be done online, but the tour agency insists it has to be done at the airport. I’m not sure which one to follow. Additionally, I’ve been prescribed a sedative for my fear of flying—am I allowed to bring it on the plane? Any help or clarification on these issues would be greatly appreciated!