5e Monster Manual / NPCs. How to edit the character sheet for just one instance of an monster?

An example: Using 5e MM, I can drag several copies of a "Veteran" into my game.  I want one of those be their leader, adding some skills, changing armor, etc.   But when I edit that token's sheet, it edits all instances of "Veteran".   How can I go about editing just the one instance?

Duplicate the character sheet, making the new one your custom monster. Otherwise as you say, it will be across all sheets for that monster.

Thanks.  Based on that hint, I think I've got it... but there's still something about the token-character sheet interaction that doesn't quite fit my mental model. 1) Search for Ogre (for example) in SRD 2) Drag ogre token into game 3) Shift-double click to open the Bio/Char Sheet/Attribute & Abilities box 4) Click Edit 5) Go down to where it shows the token, and click Duplicate. That creates a "Copy of Ogre" in my Journal that I can edit.   Just seems odd that "Duplicate" is listed next to default token, but what it does is duplicate the character sheet.  Let me know if there's an easier way that I'm missing. I don't know... there's just something there that seems weird.  Either tokens and character sheets are the same thing, or, if not, operations that work on one (like making a new sheet) maybe should be called out more?   I'd love to see the distinction made more clear.

That box that shows the token is a property of the character sheet. I.e. the character sheet points toward a specific instance of the token. If you were to open the token edit box for the token on the board, you would not be changing anything about the default token that is saved to the character sheet. The character sheet cannot edit any token properties. In other words, everything on that dialog box is still just affecting the character sheet. The "Duplicate" button's proximity to the default token is a happenstance. They are in separate "columns".