Your Adjusted Gross Income is generally the grand total of all your sources of income. As shown on the "long form 1040" it's the right-hand column summation of wages, interest, dividends, capital gains, etc., and is used
before deducting for expenses that you can remove, credits for other situations that reduce your taxes, and
the amounts that have been withheld or estimated amounts you've prepaid.
I hope this helps!