How do you know if you have credit?

If you have never applied for credit, then you don't have credit.

You develop credit by getting a loan or getting a credit card. When you borrow money that you need to repay, then you are developing credit. Auto loans and mortgages are also things that build your credit profile. If you pay your accounts on time and keep your credit card usage low, then you develop a great credit score. If you make late payments or max out your credit cards, then you develop a poor credit score.

To start building your credit, you would need to get a credit card or a small personal loan. A secured credit card is sometimes the easiest way to get approval for credit if you have never had any kind of loan or card in the past.

Checking and savings accounts and debit cards do not help or develop your credit in any way.

Paying rent, paying for utilities such as electric bill or gas bill, paying for phone service, and paying for things like internet or cable also DO NOT build your credit score. When you get these things, you are paying for a service and if you stop paying for the service, then they just disconnect you or evict you. You are not actually borrowing money to use those services. Some of these services might check your credit score before allowing you to have their services or to determine what offers they will give you, but using their services don't actually help your score.

EDIT: If you use it wisely, you can get a credit card to start building your credit. Just because you have a credit card doesn't mean you have to spend it on things you can't afford. You can use a credit card to pay for something you are going to purchase anyway. For example, you can set up your credit card to auto pay for your cell phone bill. Then set your checking account to auto pay your credit card bill on the due date of the credit card. You haven't spent anything that you wouldn't have spent anyway. As long as you are paying the credit card bill in full when it cycles, you aren't even paying interest because you would be paying back what you spent before the interest is charged. Do not pay your credit card before the bill cycles. If the credit card company doesn't cycle a bill, it is like you never used it at all and that doesn't help your score. (you can pay before the due date. Just don't pay before a bill has been cycled to show a payment is due)

You don't have credit. A bank account is not credit, nor is a debit card since you are using your own money not the banks.

You do not have credit just because you have a bank account.

You get credit by borrowing money or by getting a credit card, or by applying to do either of those things.

You would know if you had credit.