Go out in a field and walk it and start to pay attention to the ground beneath your feet.
Pay attention to basically every plant until you learn to tell the plants apart.
Take pictures. Use #inaturalist. Be systematic. Don't say "that is grass": what kind of grass? Is it different from this other grass two feet away? How would you tell?
Then after you've done that… repeat the process over the same area. Looking again at what you missed.
