In the original form of Ranger, you should be getting extra enemy types and languages at levels 6 and 14, giving you three total from base Ranger. That's how it worked in the PHB. I'm not sure what Larian is planning with their homebrewed feature, might just be extra bits, same as PHB.
Thanks for the info! Allowing players to pick additional Favoured Enemy options at levels 6 and 14 would seem a bit weird in BG3 given the way that the ones available at level 1 have been written as a sort of background to your character, which I do like. As per the OP, giving players options for spells or abilities thematically appropriate to their selected Favoured Enemy at those levels, or even more frequently, might make more narrative sense.
But as you say, it’s a home brew so there are multiple ways Larian could be planning to go.