Hi Welcome to JustAnswer
Give me a moment. I will get back to you with possible solution of it.
Have you setup a time machine application in your machine?
choose Apple menu > System Preferences, then click Time Machine
ok. Let me see why "revert to" option is not available. Did you check if this option is available in other applications/software like Text editor etc
Sure ,No problem
Alright , Just one thing which all editor(s) you are using ?
Please follow the instruction of below document
Please try to open your document in some other editor like microsoft word etc and see if you are able to see "Revert To" option under file menu.
Even after trying that you are not able to see then the reasons could be, You might have created your file in different mac and trying to restore it to previous on new mac machine.
Also check if , you have not checked the checkbox of "Ask to keep changes when closing documents", which disables the version tracking or Auto Save option.
Please check if these options are enabled
Yes, It seems to be difficult to retrieve it.