if i buy an new macbook air can I use my old imac (Catalina 10.15) as a second monitor
iMac (24-inch, M1, 2021, 2 ports)
+1 no, Macs are computers they are not external displays for other devices. If you need an external display for your new MBA please buy one, this is a:
+2 carefully read to old TDM article, at > Use your iMac as a display with target display mode - Apple Support
There are too many to list, literally over 50 at least. Just select the display size, feature set you are looking for and go from there. If you happen to live in the USA, Costco normally has a decent selection. Otherwise check your local Best Buy or local office supply store. Online, take a look at Amazon.
Have a look at > Use an external display with your MacBook Air - Apple Support
No.
Target Display Mode was discontinued years ago.
Have a look at earlier posts as this is a common question.
What is considered an external display that will work with a new macbook air?
Second monitor needed
