Keep in mind that the walk will be a bit of a hike from the Studios, and the walkway isn't that easy to find from the Studios side. There's a resort boat launch that will stop at the Yacht/Beach dock, and that's the easiest way to get there.
There is no bus between the Studios park and Beach Club. Only the boat or walking. (The walkway starts along the fence to the left of the exit, just along the lagoon side of the parking lot.)
Contrary to popular belief, you CAN use the Disney busses if you're not staying at a Disney resort if you're visiting the resort for any reason. There used to be a restriction years ago, but there's no restriction now. I think it's fun to visit resorts and eat at their restaurants.