What is a naval blockade and how would it work?

The US Navy Commander's handbook on naval operations law from 2022 defines a blockade as a "belligerent operation to prevent vessels and/or aircraft of all States, enemy and neutral, from entering or exiting specified ports, airfields, or coastal areas belonging to, occupied by, or under the control of an enemy State". US Central Command (Centcom) appears to be following this guidance, saying that the operation will be: "Enforced impartially against vessels of all nations entering