All your credit card is, is the reverse of a checking account. You’re allowed to spend first and put money into it later.

Your budget is still determined by your income. What you spend using the credit card needs to not exceed what you bring in each month. But things like grocery, internet, phone, heat, electric can probably be paid with your credit card.

Likely, you need to move from budget by account to a written budget so that you can track your credit spending.