first time user, 3 month live card/code *Riot points*

so yeah, im new here and honestly i regret buying the 3 month card because im pretty much just into single player games for my xbox and dont really need gold at the moment. so i was hoping to trade my 3 month code (im assuming i email you the code or something?) in exchange for riot points for league of legends? like a $20 dollar riot point code would be nice. so fingers crossed! hope someone can help me out!

oh and if im doing something wrong please tell me and ill do my best to fix or edit this somehow (added pictures now that i know im supposed too lol)