How can connect my iMac to my Early 2015 13 inch Retina MacBook Pro.
I want to use my iMac as a 2nd Display to my MacBook Pro. The MacBook Pro has a Thunderbolt 2 (I have that cable). The iMac (Retina 5K, 27 Inch, 2017) has Thunderbolt 3 ( I have the adapter 2 to 3). Bot running Version 11.4 Big Sur. I connect everything - hit Command F2 ... Nothing happens.