Q: run Profile Manager

Isn't Profile Manager a part of OS X server?

https://www.apple.com/osx/server/features/#profile-manager

I have only ever used it as part of OS X Server. I'd expect it to be a download from Apple.com or in the Apple store. I can only see a 'clone' in the app store that doesn't appear to be made by Apple.

Profiles can be applied to clients, I suspect that is why the articles discuss OS X client.

You may want to investigate other MDM options if you do not have a server. 'Apple configurator' may do similar things if you hope to manage iOS devices. That is in the App store.

If no one has a better answer try asking in the server section of this site - someone may confirm it in there.

Yes, that is the Server app. It enables features and provides management tools.

Server used to be a separate OS, but since around 10.7 it became an app that installs a lot of extra tools & modifies the client OS.

Once you run & use the Server app OS X is kind of modified 'for good'. Just be prepared to erase & reinstall if you need to undo it. Ideally make a full backup before if you are just testing it on your own Mac.