Yes, you must file. Firstly, you must file a schedule C to report your income, deduct expenses, and pay self-employment tax on your net profit.
Then, whether you also owe income tax depends on how your spouse will file their return. If your spouse uses the standard deduction, then you can also use the standard deduction ($13,850) which means you won't pay income tax (even though you pay self-employment tax). However, if your spouse uses itemized deductions, then your standard deduction is zero. You might have itemized deductions (charity, mortgage interest, etc.), and if your net business profit is more than your itemized deductions, you will owe income tax on the difference.
Yes, you are required to file is you have over $400 in self-employment income. Form 1099-MISC or 1099-NEC reports money you earned doing work for a client or for a company as a non-employee. Think of it as the self-employed equivalent of Form W-2. You can claim business deductions to lower your income and taxes also. Married filing jointly is usually a better option than filing separately, see links below.
How to report your Door Dash income