To add a bit to the answer you've gotten from Chitrahaas ...
The feature is currently released to people in the Insider program for Office 365. Anyone can join this program unless they're "ruled" by an IT department that prohibits it.
We have no way of knowing when the feature will be more widely/generally released, but it's certain that it'll be released only to people with O365 subscriptions, not to people running Office 2019 or prior (though I'd place a reasonable bet that if a shape's locked using O365, earlier versions will respect the lock, even through they can't create them.)
The non-subscription version of Office may receive some of the features that have been released in O365, but probably not all. Until MS makes the announcement, we won't know.