Anyone who understands even the basics of print has a greater comprehension of design over those who strictly work digital. Print is still an active medium and will always be useful for things like business cards, posters, and book covers.
InDesign is unequivocally the best program to study for any print work ranging from style guides to letterheads and corporate flyers. Thankfully InDesign is meant to play with other programs like Photoshop and Illustrator, so if you’re already familiar with Adobe software then it shouldn’t present much of a hurdle. If you’ve ever wanted to get started learning print design then take some time to read through these free tutorials and try your hand at a couple projects.