Upgrade to Catalina 10.15.7
I'm currently at High Sierra 10.13.6 and would like to upgrade to Catalina but don't know how. I would like to ultimately get Reunion software if I can with my present computer.
iMac 21.5″, macOS 10.13
Back up your data, check your applications for compatibility, click here, and if your iMac is a 2012 or newer model, then on the download link for Catalina.
Catalina and newer won't run 32-bit software; download and use Go64 as well as using the first link above.
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