Mid-2011 MacBook Air trying to upgrade OS.
I just bought a new iPhone SE, tried to connect to iTunes and was given an error. Updated iTunes, and I get a new error saying that to use my iPhone with iTunes, I need to install OS X 10.11.4 or later (currently on 10.10.5). I go to App Store and try to download Catalina — I know this doesn’t work with my Air, but I thought I would be given an option for a lower version — I get a message that says the version cannot be installed on my computer and no other options. There is a button to “learn more”, but nothing happens when I press this.
What are my options? My entire iTunes library is on this Mac.
MacBook Air