@seunkim95 , without further information and solely based on your post, I am assuming the following ( please correct/ confirm in your reply :(
1. You entered USA with a F-1 visa in 2013. Thus you would have been on "exempt" status through 12/31/2017.
2. So for the next years i.e. 2018 through your departure date in 2022 you would have been a "Resident" for tax purposes. taxed on your world income and filed a form 1040.
3. You should have filed a dual status return for the tax year 2022. A 1040 ( world income ) for the period you were in the USA and a 1040-NR ( ONLY US sourced income ).
4. From Jan 1st. 2023, you were a Non-Resident Alien, taxed ONLY on US sourced income, filing a 1040-NR ( not supported by TurboTax ) and US-Korea Tax Treaty comes into force.
5. Assuming that when you left the USA, your status changed ( either through cancellation of your F-1 visa or just abandoning your residence), there should have been a filing with Immigration that you are leaving the country and also a note to IRS informing your departure. At this point in time and assuming that you just did not inform Immigration and/or the IRS, there is not much point in taking curative actions. But you should file for an ITIN, inform your broker and financial institution(s) that your status has changed.
Is there more I can do for you ?
pk
