Barbe anxiety

I plan on going to a barber this week cuz its been like 2 years since i last got a haircut (professionally)

I usually cut mine at home but i cant help but me nervous

What the hell do i do when i walk in? Do i go and sit? Do i say hey i have an appointment booked 10:00am to the guy but he maybe would already be busy cutting someone elses hair, that maybe disrespectful? There isnt a receptionist its just 6 chairs.

What if theres no seats available in the waiting lobby

Ahhhh i dont even know lol