Mar 9, 2017 - 3:07 PM
Welcome to MySwissAlps Padoongsak!
All the retailers listed here sell print at home passes which are ready to use. No validation required. I don't know the agency you purchased from, so they might be an exception. If the travel dates are already printed on the pass, and the passenger names and passport numbers too, the pass is ready to use.
Chandraks is correct about the passport: you do need to take it along at all times.