Software Update / checking for updates...problem
The software Update where it shows checking for updates my Mac is just loading and never actually shows the update I need help please!
iMac
What year model iMac?
Identify your iMac model - Apple Support
Third party AV-ware, Cleaning-ware and VPNs can block macOS updates and upgrades.
To over come various obstacles when updating, startup in Safe Mode and then try to up update.
If an error occurred while updating or installing macOS - Apple Support