New league player

I am new to league of legends only level 19. been playing for a couple weeks now. After I get OWNED by a team I will check and see most of the people in the lobby are gold/plat and even emerald players in ranked. There account level is 500+. Why am I matchmaking with them... Its so frustrating to learn league already and I get a guy way way way better than I am. Not other noobies...