After an MDM profile is created by someone technical, it can be emailed to the non-technical user and installed with a few clicks and passcode confirmation.
Can I enroll my personal iPhone in MDM myself? And if I can have MDM with just my personal phone, do I need to buy some kind of subscription for it from Apple? Or pay some third-party?
I thought MDM was only for enterprise businesses and schools and universities, but I may very well be mistaken about that.
MDM profiles are just XML files. They can be created with any text editor and distributed to the phone by email or web server. Apple provides the free "Apple Configurator" app in the MacOS app store. There are also websites and/or OSS tools to generate profiles, e.g. https://github.com/ProfileCreator/ProfileCreator.
^^^ Highly recommend this. If you are technical enough, a family managed Apple Configuration is more than enough to protect for most situations and from most threat actors.
If you're threat actor has the resource to break that, get a CC or a good lawyer on retainer I guess.