Lights are a must, unless there's a 0% chance you'll run across drivers or other cyclists on your route.
But there are some other considerations to take into account, aside from just having lights. Many modern bike lights are over-powered and don't have cutoffs like car headlamps do, and these can easily blind oncoming bike traffic on the sort of multi-use trails I commute on, especially if they're helmet-mounted. I'd highly recommend StVZO-compliant lights if you're riding anywhere near other cyclists, to avoid blinding them. I use StVZO dynamo-powered lights on my commute-to-work bike, and on my cheap do-errands-around-town bike I use these:
https://www.walmart.com/ip/MEIDI-Bic...ight/704688630