Create note or text file in 1 shortcut, check if it exists from a 2nd shortcut - HOW?

I’ve searched all over, posted to Reddit and Discord and forums and…. I can’t seem to get an answer. I don’t understand why this is so difficult!! It has to be doable, isn’t it?

Create note or text file in 1 shortcut, check if it exists from a 2nd shortcut - HOW?
 
 
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