What exactly do you want to do with your Armory wallet?
If you want an offline mode wallet then you can just directly use them without Bitcoin core and internet there is two option when you are going to open the armory wallet look at the image below as a reference.
As you can see there is Armory and Armory(offline) and other two testnet and uninstall you can choose Armory(offline) if you want to create a wallet with offline mode.
Or if you want to use it online choose the Armory icon only and to fully use the function of this wallet you will need to install Bitcoin core and wait to fully sync just like the above suggestion you must disable the pruned mode on Bitcoin core.
