I would focus on just the one for awhile, to be safe. Spend wisely and pay off monthly until done. If you’re doing well on that loan or pay it off, as far as payments and being on time, then you can consider a starter card. Just remember, you have to know yourself and your spending habits as well as your self-discipline before you get a credit card. Check out Dave Ramsey’s financial advice on credit, he’s helped millions of people get a realistic view of credit and debt. Highly recommend you read the book.