How to tune a NEW viola and how to fix the bridge?

Well today i just got a new viola, its like new new. And when it came the strings were loose and it sounded funny and also the bridge is really weird, like isn't there suppose to be a little slit where the string goes on the bridge?? I am sooooo stressed!! i dont really wanna ruin a freakin expensive instrument without even using it!! my parents would kill me!! PLEASE I NEED HELP!! i need help most on the bridge part and the bridge is not even.. and on the instructions it said to sand it or something.. i was like wtf.. pleaseE HELP! :]