How to enter the U.S. by land from Mexico when the border is opened

A week away from the U.S. Government opening its land borders with Mexico and Canada after 20 months closed to foreigners due to the Covid-19 pandemic, more details are known about the requirements to be able to enter the country.

How to enter the U.S. by land from Mexico when the border is opened
U.S. - Mexico border. Image: Agencies