Explain what you're asking with this.
High Sierra is, as far as I've heard, supporting the mid-2010 and newer MB Pros.
https://en.wikipedia.org/wiki/MacOS_High_Sierra#System_requirements
Whether a mid-2012 MB Pro will keep supporting the OS to 10.14 or 10.15 (or even later), I don't know.
Most likely 10.15 will work on the 2012 MacBook Pros which is fine for me.. this thing is so upgradable, I am not sure I want to go past 2012 because they are no longer upgradable.