Step-by-step upgrade OS X and Parallels versions help

Currently running OS X 10.10.5 and Parallels 11.2.3

Need to upgrade OS X to High Sierra and probably to Mojave right now.
I have Parallels v12.1.1 and Parallels 15.1.2 upgrade versions that I purchased but never installed.

I want to upgrade OS X version-by-version (ie. start with 10.11 and move upwards) and co-ordinate that with upgrading Parallels.

My question is - what versions of Parallels should I install at which point in the OS X upgrade process?

Thanks for any advice.

 

Hello, please check this KB article out for more information about Parallels Desktop and macOS compatibility.
Please let us know if you have any additional questions.