You need level 2 Vanguard to buy legendary gear. Unequip the faction class item and do strikes to get Vanguard 2. On my first character I was level 28 with two blues and two legendaries after hitting rank 2 and then could ease into endgame content. At 28 you're two weeks away from buying an Exotic armor piece from Xur from running the weekly heroic. What system are you on?