Force Updating Older Mac

Jaxon-M-Lester wrote:

So, I have a Early-2015 MacBook Air, and it only runs MacOS 12.7.6. I need to update to MacOS 18.

Sequoia is macOS 15.

How can I do this, because it says I have the newest software (macOS Monterey).

You have the newest compatible operating system for that model. Monterey is six or seven major versions beyond what was on that machine when it was new in the box – but it's also the end of the line. There are applications that you can get such as Firefox and LibreOffice whose current versions will run on Monterey, but if you are looking for software from the likes of Microsoft, Monterey is unfortunately no longer one of the "most recent three."

Identify your MacBook Air model - Apple Support

If you need to run something that requires a current version of macOS, you will need to get a newer Mac.

The most direct comparison would be with the M4 MacBook Airs:

• Size and weight: Your Mac has a 11" screen and weighs 2.38 pounds. The M4 MacBook Airs come in 13" and 15" sizes; the 13" one weighs 2.7 pounds, and the 15" one weighs 3.3 pounds.
• Performance: The M4 machines have much faster CPUs and integrated GPUs, much more RAM (16 – 32 GB vs. 4 – 8 GB), and more modern, faster, expansion ports.
• macOS compatibility: The M4 machines can run Sequoia and will be able to run many future versions of macOS. They also have Apple-Silicon-only features like Apple Intelligence, and the ability to run some iPhone/iPad apps – if the developers of those apps choose to allow it.
• Screens: The M4 MacBook Airs have Retina screens.

Basically, if you went from your 11-inch Early 2015 MacBook Air to one of the M4 MacBook Airs released ten years later, you would be looking at huge upgrades in just about every respect except for weight. Ten years of year over year hardware updates do cumulatively make a difference!

That model can't be upgraded past Monterey.

(260715)

You can't.