Can i schedule my biometrics appoinment via infopass right after receiving I-797C?

the NOA says they will send me a letter with the date of my appointment but i have to travel outside the country on june 10 and i do not think they would schedule my appointment before this date. i want to know if i can schedule myself or do i have to wait for them to give the date so i can reschedule? is there any way i can do the biometrics in a us embassy in the country i am going to travel?