I agree with @CyanoticWasp. Write it yourself and tell people those are the things they should mention in addition to whatever else they wanted to say.
But why do this? I know the NYT and other news organizations have pre-written obits for important people in case the person dies. They have to update them from time to time.
I know that our loved ones have a lot of stuff to do when we die, and writing an obit is not one of the things they want to do then. Besides which, you don’t know if you need 2 column inches or 20.
Another thing you could do is set up a web page for memories of yourself or someone else. They could be private web pages that go public upon death.