((Not a teacher))
Shore:- The land along the edge of sea, river or broad lake.
-- The ship will reach the shore shortly.
Beach: An area adjacent to a sea shore; the expanse of sand along the shore.
-- The children played on the beach.
- We made sand castles on the beach.
Coast: If refers only to land along an ocean/sea.
--They live on the coast in a beautiful house.
Coastline: The outline of a coast.
-- I could see the coastline from the distance.
--The coastline could be seen from the ship.
Hope the above clarifies.