For the EITC, I have one child and made 38k in 2020. According to the table I looked at online, I should be getting back 3,584, but instead I'm getting 538. Any ideas?

https://ttlc.intuit.com/questions/1899157-what-are-the-qualifications-for-the-earned-income-credit-eic-or-eitc

https://www.irs.gov/credits-deductions/individuals/earned-income-tax-credit/use-the-eitc-assistant

You are expecting to get back the maximum amount ----the EIC is calculated on a bell curve.   You are getting almost to the limit of not getting any EIC--- so if you have one child and your income was $38K, the $500+ you are getting is correct.

Look at the IRS table for EIC.  Your income is on page 36

https://www.irs.gov/pub/irs-pdf/p596.pdf