I think you could probably pull specific TNG episodes out that will not only show who Picard is, but also give a few glimpses of characters/races that will be involved in Picard

Honestly though I believe Picard can be enoyed as a show on it's own, it feels a little like Star Trek mixed with Guardians of the Galaxy/Solo movie, mixed with the quality of a good hour long HBO drama show. There is a few familiar old people faces lol, but the show is really a great new "crew" and cast of characters with Picard being the only recurring old one. The show is awesome, it isn't even done and already can't wait for season 2, especially knowing things like this occurred