Can I upgrade my MacBook Pro from High sierra to big Sur even if it is from 2012?

No but you can upgrade it to Catalina.

The model year of a MacBook Pro is available at Apple menu > About This Mac.

A mid-2012 through early-2013 MacBook Pro can be upgraded to Catalina 10.15.7 but no later version. See: https://support.apple.com/en-us/HT211683

A late-2013 or later can be upgraded to the current version of Big Sur. See: https://support.apple.com/en-us/HT201475

Matasverdes wrote:

Can I upgrade my MacBook Pro from High sierra to big Sur even if it is from 2012?

Catalina 10.15.7 is the end of line for your hardware—

the older macOS installer backups on this server:

https://support.apple.com/en-gb/HT211683

verify you are using the Safari browser to download/initiate the macOS links.