My Mac was stolen, how do I know that it had Find My Mac enabled? I never did it manually.

I don't remember if it defaults to on but you may want to check the following. Go to any computer and log in to https://www.icloud.com/ and then click on Find My iPhone there and see if it is in the list of your "All Devices."

The following link has some other information that may be helpful: If your Mac is lost or stolen - Apple Support

Evelyn_GrayLineDR wrote:

Thank you FoxFifth, for your reply, this is very helpful. By the way, my Mac is listed in "All Devices"!

That is good news.