You can drink herbal tea, if you want flavor but no caffeine. I just put a bag in cold water, and it steeps just as well.
But I rarely do caffeine, myself. On occasion if I’m feeling it, but I prefer to go without most days. Water or carbonated water are my standard go-tos.
I don’t drink caffeine either because of a bad experience with really strong espresso.
I still crave the taste of coffee due to being a simple animal with habits, so I’ve switched to decaf espresso with beans that went through a swiss water method (literally runs the beans through water and filters out the caffeine). That’s only if you like the flavor of coffee though, most commercial decafs use a chemical solution to remove the caffeine.
Otherwise water, and I love seltzer