I see some people doing wood engraving where the engraved part is lighter -

I see some people doing wood engraving where the engraved part is lighter - how is that achieved? Do you stain the wood, then engrave to a depth that reveals unstained wood beneath?

Example: https://img0.etsystatic.com/134/0/9493600/il_570xN.854222626_q1sd.jpg

In that image you shared, I’d imagine you are correct that the wood is stained & the imagery engraved afterwards. As that looks like typical plywood that has definitely been stained.

Stain… mask…engrave… paint before removing mask