The main difference between Veranda and Porch is that the Veranda is a roofed, open-air gallery or porch and Porch is a construction.
A veranda or verandah (from Portuguese varanda, IPA: [vɐˈɾɐ̃dɐ]) is a roofed, open-air gallery or porch. A veranda is often partly enclosed by a railing and frequently extends across the front and sides of the structure.
Although the form “verandah” is correct and very common, some authorities prefer the version without an h (the Concise Oxford English Dictionary gives the h version as a variant and The Guardian Style Guide says “veranda not verandah”).
A porch (from Old French porche, from Latin porticus “colonnade”, from porta “passage”) is a term used in architecture to describe a room or gallery located in front of the entrance of a building forming a low front, and placed in front of the facade of the building it commands. It can be defined more simply as a “projecting building that houses the entrance door of a building or as a vestibule, or hall.
The porch exists in religious architecture as well as in secular architecture and is found in different forms and structures, built from various materials around the world.
A gallery, platform, or balcony, usually roofed and often partly enclosed, extending along the outside of a building. from 18th c.
A covered and enclosed entrance to a building, whether taken from the interior, and forming a sort of vestibule within the main wall, or projecting without and with a separate roof.
A portico; a covered walk.