I have a Mac book pro with OSX 10:11.6 and how do I upgrade to OSX 10:13.6.
How do I upgrade to OSX 10:13.6 from an OSX 10:11.6 on a Max Book Pro ?
MacBook Pro 15″, OS X 10.11
How do I upgrade to OSX 10:13.6 from an OSX 10:11.6 on a Max Book Pro ?
MacBook Pro 15″, OS X 10.11
Does it qualify?
macOS High Sierra - Technical Specifications

General Requirements
Mac Hardware Requirements
For details about your Mac model, click the Apple icon at the top left of your screen, choose About This Mac. These Mac models are compatible with macOS High Sierra:
Don't use Firefox as it’ll mess things up…
https://itunes.apple.com/app/macos-high-sierra/id1246284741?mt=12
Does it qualify?
macOS High Sierra - Technical Specifications

General Requirements
Mac Hardware Requirements
For details about your Mac model, click the Apple icon at the top left of your screen, choose About This Mac. These Mac models are compatible with macOS High Sierra:
Don't use Firefox as it’ll mess things up…
https://itunes.apple.com/app/macos-high-sierra/id1246284741?mt=12
I have a Mac book pro with OSX 10:11.6 and how do I upgrade to OSX 10:13.6.