Im running Big Sur 11.7.4 and I cannot update pages

Pages v11.1 is the last version compatible with Big Sur (11.*). If you have that version, you are done as the current version of Pages available from the Mac App Store requires macOS 12.3 or later.

If your version of Pages is older than 11.1, then provided you have installed Pages previously from the Mac App Store using the same Apple ID, you can launch the Mac App Store, sign in with that Apple ID, and press cmd+0 (zero) to open the Purchases panel. If Pages appears there with a blue cloud download icon, or Update button, click that. A dialog will appear offering to install the last compatible version of Pages for macOS Big Sur.

If you never orginally installed Pages via the Mac App Store, or if the Mac shipped new with Pages pre-installed by Apple, then you are done with the current version of Pages that you have, and may need to resort to Pages for iCloud.

If you can get access to your own account on a computer with the required minimum macOS version for the current version you can purchase/buy the app on it. Now go to your old computer and bring up _your list of previous purchases_ (the previous purchases part is important - see the tip at How can I get Garage Band for OS 10.14? - Apple Community ) in the Mac App Store application. Try downloading it. It will say the current version will not work on your computer but may offer an older version if one is available.

If this is an app that interacts with a service offered by the developer (e.g., YouTube or Netflix) there is no guarantee the old version will actually work with the service, but I have found some old versions are available and provide partial functionality.

Despite what may or may not eventually be recommended for you to read, I know this works in June 2023, and has for several years now. In 2019 I had access to a Mac running macOS 10.15. I downloaded Pages on it and was able to get an older version from my purchase history in the Mac App Store on another computer with macOS 10.9. In 2023 I was given a 2013 Mac Book Pro running macOS 11. I went to the App Store and it said the current version required at least MacOS 12 to run, did I want to download an older version? I said "yes" and it downloaded the version compatible with macOS 11.

If for some reason you cannot get Pages to update using the method I provided (and VikingOSX reiterates) you can try running pages in iCloud with a web browser at iCloud.com.