🚀 go-pugleaf

Where do I find the first key in level 6?

It's the one where you start by the bamboo gate and round the corner
into an area with a waterfall into a lagoon. The only way out is
underwater.

There are also four buttons in what I would call a shrine room. You
enter facing a statue, go up the stairs to either side and turn and
face the door, there are two columns with a button at the top and
bottom of each. What do the open or unlock. I've heard the sound of
something but haven't found what it is.