@Meongtae
question - have you filed taxes in 2018 or 2019?
if yes, then you should be checking here . Your AGI is line 7 on the 2018 return and line 8b on the 2019 return.
https://www.irs.gov/coronavirus/economic-impact-payments
if no, then you should be filling out a simple form here:
https://www.freefilefillableforms.com/#/fd/EconomicImpactPayment
