TNG is, imo, the gold standard and an excellent starting point if you’re not looking to jump straight into Strange New Worlds. Its episodes are generally pretty self-contained, so you won’t be punished terribly for jumping around if you’re just looking to get a taste, and will still be able to enjoy the great episodes it has to offer, but you will get more context the more episodes you’re willing to watch.
Plenty of folks have compiled lists of which episodes are skippable vs worth watching, and there’s pretty universal agreement on which are iconic must-watch episodes, so there’s nothing wrong with following one of those for a first watch. Here’s an example.I’d recommend using the list at the bottom of that page (or another rated list) as a guide, and experiment a bit to figure out a good baseline for how low of a rating is acceptable and how many episodes you can tolerate in your first watch through.
Note that season 1 is widely regarded as the weakest, where the show is trying to emulate ToS and hasn’t yet come into its own, and you can skip episodes more liberally here, or even come back to it later.