Federal law will ALWAYS override state law. This is due to the supremacy clause.
The law (supremacy clause) that applies to situations where state and federal laws disagree is called the supremacy clause, which is part of article VI of the Constitution. The supremacy clause contains what's known as the doctrine of pre-emption, which says that the federal government wins in the case of conflicting legislation.
Here's an article to help you further:
https://m.huffpost.com/us/entry/us_4676579
Have a great day!
