Start with one fixture, not a league
People give up on a new league because they try to absorb it all at once: eighteen or twenty clubs, unfamiliar squads, and a table that means nothing to them. The fix is to watch the same weekly slot for a month. By the fourth week you recognise coaches, referees and the two or three players who decide matches, and the league stops being a wall of names.
The late Sunday game is the natural choice because it is the fixture everyone involved has prepared for: the presentation is better, the crowd is fuller, and the match usually involves at least one side with something to protect.
Pick a team for the wrong reasons
Neutrality is overrated as a way of enjoying football. Choose a club because you like the badge, the city, the coach's stubbornness or the fact that they play a teenager at left-back, and the same match becomes twice as interesting. You do not need to be a supporter to benefit from caring about an outcome for ninety minutes.
The added advantage in France is that the club you pick will very likely be developing someone worth watching. A season later you will see him in another league and know exactly what he can and cannot do.
What you will actually see
Expect matches that are more physical and less controlled than the highlights suggest, with transitions that arrive quickly because teams commit players forward and are punished for it. Expect refereeing that allows contact. Expect at least one goal that would be described as chaotic in a more polished league.
That is a recommendation rather than a warning. If you want your football tidy, there are better places to look; if you want it to feel unpredictable at eight in the evening, this is a good hour to spend.