What you have is a punch, but a modeller's punch-and-die set looks like this:

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You place the sheet (plastic, pewter, decal sheet, whatever) between the clear and the steel plates, tighten the screws at least somewhat, insert a punch into the appropriate hole, and tap it with the hammer to create a neat little disc.

It's a tedious job, and glueing a bunch of those discs or rivets onto a model is often even more tedious, but depending on what you build, it can be a life sanity saver  Like when you find yourself having the brilliant idea to build something like this:

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