Even if you're pulling in 100% of your income through a W-2 job and you're sure you're not itemizing, you have to consider excluded income, above-the-line deductions, and refundable and non-refundable credits. Oh, and do you live alone or might you claim a dependent,[1] and on and on and on. People spend their whole lives on this stuff and still don't understand the half of it.

[1] https://drive.google.com/file/d/1xtyyMPczy6nuj_QR4Jy4J8sf8f3...