"We are going to the beach."
Translation:Мы идём на пляж.
Don't pay much attention, as I am still learning as you, but I think that'd mean "We are walking to the beach" Like emphasizing the WALKING part with that word. Is IMO something you would say if you are at a hotel that is just two blocks away from the beach, as opposed to one that is 30 minutes away(Who would stay in a hotel 30 minutes away though n.n)
Ходить/идти refers to "going" but usually implies going by foot somewhere, and it is typically reserved for smaller distances (going to a store, going to school, etc.). Ездить/ехать is "going" but implies by means of some transportation (car, bus, plane, etc.), and traveling bigger distances (traveling between cities, countries, etc.).
You can use them interchangeably if you add words like (идти) пешком (to go by foot) or (ехать) на автобусе (to go by bus), if you really want to clarify the meaning of something. Like you can't just say "Я ходил в Китай" (I went to China), unless you actually DID walk to China, in which case it's better to add пешком to clarify that that's what you meant.