Trying to find specific embossed grid paper
I haven't seen paper with such an embossed grid, but you can use regular paper over a plastic grid that does that.  They're typically called something like a "freehand drawing grid".  There are several brands, like "FreeHand Designer" and "Accu-Line Grid".  You put it under the paper.  The surface has tiny pyramid-shaped bumps that keep your pencil going in a straight line.  This is what the surface looks like magnified:



You can find them on Amazon, as well as other places.  Here are a couple of links to get you started: FreeHand Designer and AccuLine Grid.  They're available in various sizes.