Unless a Pokemon is separately programmed to know specific moves, they know the last 4 level up moves from their level or lower.
Eevees hatch at level 1. Unless they inherit certain moves from their parents, they'll hatch knowing the last 4 level 1 moves, which are helping hand, tackle, growl, and tail whip. They don't know covet because covet is listed before those other 4 moves.
Eevees can know covet if both of their parents knew covet, or if the move reminder teaches covet to them.