Making a in editor public writing prompt

I’m trying to figure out how to make a writing prompt in my scripts details panel so I could write a string in the writing prompt that would lead to a tag or another script. I have never tried this sort of thing, and i’m unsure if it would even work or how to even try this. If there’s any suggestions or advise of how to try this, much appreciated.

Not quite sure what you mean.

public string tag;

GameObject player = GameObject.FindGameObjectWithTag(tag);