18 year old girl looking for accommodation in Munich

i`m Carolina Gutierrez, 18 years old and i,m from Mexico, i`m a very polite and respectfull person so you will never have trouble with me, i.m already in Munich but unfortunately i`m staying in a hotel so i can`t renew my residence permit i came here for studies so i`ll stay for more than a year i`m not looking for anything in special just some flat or room big enought for one person, i prefer it to be near some train, tram or subway station so i can get faster to my classes, if anyone knows anything please let me know cause i really need the place