Time Capsule how to see which Macs are backed up
Time Capsule how to find a backup for a specific Mac
Restore your Mac from a backup - Apple Support
Presumably, you assigned your Macs specific names such as "iMac1", iMac2", "Betty's iMac", "John's iMac"... etc. If you do not do that, it will introduce uncertainty when choosing which backup to restore.