Unable to update my MacBook Pro 2012 past macOS 10.13

Sources suggest you may have a bit more possible upgrades, as far as 10.14 Mojave or 10.15 Catalina.

The built-in software UPDATE function automatically provides minor updates to the currently-running major version.

if you want to UPGRADE the major version, you will need to look here for the software:

How to download and install macOS - Apple Support

In general, only appropriate versions for your specific Mac can be obtained this way.

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10.15 Catalina software obsoletes any Apps that are not 64-bit ready. You may wish to check your apps using this free software before making that jump:

https://www.stclairsoft.com/Go64/index.html

In addition, later versions of MacOS re-organize your boot drive to accommodate Apple File System. The risk for data loss is slightly higher because of that. You MUST have a Trusted backup at hand before ANY such upgrade.

MacTracker indicates that all MacBook Pros released in 2012 can be upgraded to Catalina.

So does macOS Catalina is compatible with these computers - Apple Support .

Note that Catalina breaks 32-bit applications. On the other hand, Catalina is just enough to run current versions of Firefox, LibreOffice, and the commercial Affinity V2 applications (Photo, Designer, Publisher). (It isn't good enough to run current Microsoft and Adobe software, or most other major third-party Web browsers.)

How to download and install macOS - Apple Support

P.S. – This is a user-to-user forum. Apple mostly is not here, and so probably will not see your remark that "I have your product …"

The 2012 Mac book pro cannot update further then 10.13. Due to hardware limitations, that Mac is too old to run any newer iOS version