Go to the World showcase section of EPCOT, go past England and bear right up a small hill. There you will exit to the EPCOT resorts. Beach club is about a 10 minute walk from the exit. You can take a boat ride to the Beach Club resort if you want but it will be slower.
Take one of the water way boats from Epcot lower end up to the World Showcase dock nearest to France. At France is a boat and walkway to the Boardwalk.
The PPs have answered your question on how to get to B&C, but just curious- do you have an ADR? B&C is very popular and almost never takes walk-ups at dinner time.
The PPs have answered your question on how to get to B&C, but just curious- do you have an ADR? B&C is very popular and almost never takes walk-ups at dinner time.