If the funds received from an individual are not loans or they are not payment for services rendered, then they would be gifts. Gifts are not reported on a federal tax return, regardless of the amount received.
Since the gift is from a foreign person, if the gift received during the year is $100,000 or more you will need to report the gift received to the IRS using Form 3520. The form 3520 is an informational form only not a tax return.
IRS Form 3520 - https://www.irs.gov/pub/irs-pdf/f3520.pdf
IRS Form 3520 instructions - https://www.irs.gov/pub/irs-pdf/i3520.pdf