Mexican keypad in a MacBook pro

Basic keyboard glyphs are shown in this article:

How to identify keyboard localizations - Apple Support

Not sure the picture will show.

It appear that the dash and underscore are on the key to the right of the Period (just to the left of Right-Shift)

what does it give you?

this article show how to use the keyboard viewer:

Use the Keyboard Viewer on Mac - Apple Support

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