Are you using CLI or CCA?
You can configure a blast group in 5 seconds to make the phones all ring on inbound.
Look at sh run and make sure they are dual line ephones.

GUI is very easy for the TDM phone guy to learn.
(I know, I was one for 25 years)


CCNA
CCNA Voice
MCSE W2K3
Security +
CS1000 5.5
Toshiba
Comdial
Avaya
Mitel
Norstar