how do I update my 2011 mac pro from os x 10.9.5 to a newer update?
How do I update my 2001 macbook pro from os x 10.9.5 to a newer version.
Your 2011 MacBook Pro will support macOS 10.13 High Sierra.
Use Safari with this link. This will open a page in the App store from which you can download the installer.
On the same page verify your hardware compatibility. Run a Time Machine backup before you apply an upgrade.