Connect iMac 2019 to Macbook Air 2017
I'm trying to connect my Macbook Air 2017 to iMac 2019 so I can use the iMac as my dual screen. My Macbook Air has a Thunderbolt 2, so I bought a Thunderbold 3 (USB-C) to Thunderbolt 2 Adapter and connected that to the Thunderbolt cable to the iMac - I pressed the Command + F2 on the iMac and still nothing happened.
Did I buy the wrong cables?
Do I need to buy something else?