Your annual gross income is the amount of money you have made over the past 12 months before deductions (i.e.: Taxes, Insurance, etc.) Your annual gross income can be calculated using the last 12 months at the time you are signing up for Ambition Card.
Your annual gross income and estimated monthly debt are required fields to comply with financial regulations. Using your best estimate for both fields is okay. Submitting $0 is ok too, it's not a factor for whether you can open an Ambition Card account or not.