Switching between 2 screens on iMac
Recently I started having 2 screens on my iMac (2012, OS10.15.7) without knowing how this happened, and I don't know how to switch between the two. Now I am often unable to find the window of the app I need.
I would REALLY appreciate it if you can tell me how to get rid of the two screens, or to switch from one to the other!
iMac 27″, macOS 10.15