A foreign Trust is a Trust that was established in a foreign country and is subject to that country’s laws.
having a bank account outside the US is in and of itself, not a foreign trust.
are you asking about item 8 on schedule B
here's more info
Line 8. If you received a distribution from a foreign trust, you must provide additional information. For this purpose, a loan of cash or marketable securities is generally considered to be a distribution.
See the Instructions for Form 3520 at IRS.gov/Form3520 for details.
If you were the grantor of, or transferor to, a foreign trust that existed during 2023, you may have to file Form
3520. If you were treated as the owner of a foreign trust under the grantor trust rules, you are also responsible for ensuring that the foreign trust files Form 3520-A. Form 3520-A is due on March 15, 2024, for a calendar year trust. See the Instructions for Form 3520-A at IRS.gov/Form3520A for details.