How US tax filing actually works
US employers withhold estimated tax from each paycheck, but that is only a prepayment: every year you file a federal return (Form 1040 series) reconciling what you actually owe, plus a state return in most states, generally by April 15. New arrivals are often "nonresident aliens" for tax purposes in their first years, depending on visa type and days present, which changes which form applies and what income is taxed. Students on F1 visas have special rules, including exemption from Social Security and Medicare taxes for a period. Free filing options and university tax workshops exist; use them the first year rather than guessing.