using imac a a monitor
Apple iMac "Core i5" 3.0 21.5" (4K, Mid-2017) can I use this imac as a display
iMac 21.5″ 4K, macOS 10.15
Apple iMac "Core i5" 3.0 21.5" (4K, Mid-2017) can I use this imac as a display
iMac 21.5″ 4K, macOS 10.15
No, it's too new. See:
Use your iMac as a display with target display mode - Apple Support
using imac a a monitor