can I upgrade a Mac air mid 2011 to newest OS?

It can't be upgraded past High Sierra.

(210367)

No. High Sierra (10.13.6) is as far as it can go.

LadyBuggzzz wrote:

Why can't we upgrade from High Sierra OS to more current OS?

Because your Mac is not supported, unfortunately. It's too old.

Jack

Because Mojave and above require a Metal-capable graphics card.

(211272)

Why can't we upgrade from High Sierra OS to more current OS?