You're probably already taking walks. But it might be fun to give yourself a challenge. Could you, for example, guess when each house you pass was built, within, say, 20 years? Or, in the woods, how many kinds of trees can you identify without their leaves? How many signs of spring or animal tracks can you find? How many kinds of cars can you identify?
Walking and shooting
A wise photographer's best advice for great pictures: "Find something interesting and point your camera at it." You could record evidence of our current self-isolating lifestyle: empty parking lots, people walking 6 ft. apart. You can give yourself photo themes: extreme close-ups, things getting ready to bloom, interesting trash, feet, leaves, potholes, melting ice, etc.
Free books, print and audio:
As much as you may love reading, the eyes eventually grow tired. Try listening instead:
Librivox has a gazillion titles. A couple of caveats: these aren't going to be hot best-sellers; these are mostly out of print (or they wouldn't be free!). They're read by volunteers, so there will be variations in quality. Have some ideas about what you're looking for; the catalog is large. You could also try the Digital Book site:
https://librivox.org/ or https://www.digitalbook.io/
Don't forget Project Gutenberg for classic ebooks. Multiple formats, so you can read on a laptop, Kindle, and more.
http://www.gutenberg.org/wiki/Main_Page