Mac 21.5(late 2013 using High Sierra ver. 10.13.6 can I update my OS?
I MAC 21.5 LATE 2013 MODEL ME 086LL/A USING HIGH SIERRA VER. 10.13.6 Can I upgrade this computer to a later OS ?
iMac 21.5″, macOS 10.13
Question marked as
A late 2013 iMac can be upgraded to Catalina. See the following from Identify your iMac model - Apple Support
iMac (21.5-inch, Late 2013)
Model Identifier: iMac14,1
Part Number: ME086xx/A, ME087xx/A
Newest compatible operating system: macOS Catalina
A late 2013 iMac can be upgraded to Catalina 10.15.7 but no later. See: How to download macOS - Apple Support
Be aware that if you upgrade to Catalina 10.15 or later you will also need to update any non-Apple 32-bit apps. See: https://www.macworld.com/article/232735/how-to-check-if-mac-software-is-32-or-64-bit.html