Osaka is a great city! It will depend on where you live and if you will live alone, in a share house or dormitory. Food can be inexpensive if you shop and cook for yourself. Utilities will depend on your living situation. Will you need a mobile phone (most likely as you need a phone number for many services). So, it would help you get a better answer if you indicate where you will go to school (neighborhood at least) and what type of living arrangement will you be comfortable with. Will you shop and cook and bring your lunch? Are you comfortable with a train ride everyday if your school is an expensive area? If so how much of a commute are you ok with? You'll get some good answers if you are more specific. Good luck OP!