upgrade high sierra to ?
Greetings. I have iMac late 2013 running High Sierra 10.13.6. I need to upgrade to 10.14 or 10.15. What I have read says that this should be possible, but I have been unable to find them, much less do so. Have tried Software Update, App Store, etc., etc. The only os that ever appears is Big Sur, which this computer cannot handle.
Perplexed.....
Thx for the help.
iMac Line (2012 and Later)