Update 2011 Macbook pro to 10.13.6
I have a 2011 macbook pro (MacBookPro11,2) that is currently running 10.12.6 and I have some software I need to run that requires at least 10.13.6. All the references I see says this system can run that version, but not higher. But when I go to the app store and look for updates it says none are available. How can I get that version on my system.
MacBook Pro 15″, macOS 10.12