non-rev travel

I'm not sure if this is a silly question, but I'm about to become a registered companion (lucky me!) and want to know if I'll have a separate login to book my travel. I had understood that employee website and logins are confidential and secure. Anyone know the answer?

Just tried to list for flights this coming Friday/25th in First Class on Travel US.  When I went to complete the listing, it said  Purchase Premium Cabin Upgrades You do not have sufficient premium cabin upgrades for this itinerary based on mileage and passengers selected. To continue booking...