Crude oil is not a fungible commodity. Refineries can process only certain types of crude. Also, depending on logistics (delivery of crude to refineries), a country could be simultaneously exporting crude in one region and importing it in another.

The US was a net-exporter of energy in 2020 (and maybe 2019) but decided since then to become a net-importer.

That said, refineries are actually somewhat specialized wrt what kind of crude they can process. The US produces some types of crude in excess of its capacity to refine said crude and has more capacity to refine some types of crude than there is domestic supply.

Note also that the Canadian fossil fuel industry is somewhat intertwined with the US fossil fuel industry. The same is true wrt Mexico, albeit to a lesser extent.

US produces mainly WTI but refineries are set up to process mainly Brent.