dual monitors
How can I display a separate program or Chrome tab on a second monitor
iMac 21.5", OS X 10.11
How can I display a separate program or Chrome tab on a second monitor
iMac 21.5", OS X 10.11
Drag it to the external display.
Please read Apple's instructions in https://support.apple.com/guide/mac-help/use-multiple-displays-mchl7c7ebe08/mac
It sounds like you are wanting an Extended Desktop setup
dual monitors