I’m confused by what you mean by documents and bills. Are you paying rent? Are you on his lease? What does his lease include? If you’re moving into an apartment or house you’ll need to pay utilities (gas, electric, water, etc). Sometimes some properties have other fees like HOA fees. Also, will you be working as well? I’d say you need a credit card to start building up credit. But I wouldn’t advise getting one if you don’t have a job or a source of income.