Cannot update OS X software on MacBook Air
I deleted a former user on a MacBook Air 11" Early 2014 and after problems with the startup disc was finally able to install OS X 10.9.5 using internet startup.
The MacBook is currently running fine on 10.9.5 (Mavericks), but Software Update offers no access to a newer OS X. Obviously I cannot use Photos, which links seamlessly to my iPhone on a newer and larger MacBook.
I want to travel (on a motorcycle) with the MB 11" since it is much more compact.
Can anyone tell me up to what OS the Early 2014 MacBook Air 11" can efficiently work and how I can get access to a software update to install that OS?
Thanks in advance
MacBook Air 11″, macOS 10.15