How do I force macOS to update? [duplicate]

You should be able to download an update manually.

Generally speaking Apple releases what they call combo updates that will update all previous versions of an OS release to the (current) latest version.

You can search out "Mac OS 14 combo update" and you will end up here:

https://support.apple.com/kb/DL2000?viewlocale=en_US&locale=en_US

With the latest revision of macOS Mojave 14.5.

This also works with previous versions of macOS. Combo updates are also a good way to fix a "misbehaving" OS installation.