I Want to get braces but first i wanna kno what kinda problem i have with my teeth(crossbite,overbite)lke dat ?

okay So My Bottom Teeths Is Straight Except For The Two In The Middle One Is Higher Than The Other And It Kinda Makes The One Dats Short Moves Back As It Get Higher. And When I Bite Down On It My Top Teeths Wont Touch My Bottom Teeth Because That One Tooth At The Bottom That Stops It. And Sometimes When i Talk i Slur My Words Like i Cant Hold Back My Spit i Jus Wanna Kno What Is Dat Called ? If i Do Have To Wear Braces How Long???