You're so close to being able to explore the world and actually play the game, of course I'll help!
First and foremost, you will have a much better experience overall if you download one of the native builds for the game, but I know not everyone is comfortable doing that (or maybe you have a Mac, which we don't support). If you want to stick to browser, we've noticed that our game works much better in Chrome than Firefox.
The game defaults to having the TTS voice volume at 80%, so there's a little room to turn that up, but if it still sounds too quiet, the other option is to turn down the music and sound effects volumes to compensate. The best time to do this is as soon as the game starts, when you start hearing my voice. If you pause then, there will be no music or other sound effects playing at all. You should hear the pause menu say "Settings" to let you know that is currently selected in the menu, so you can then press the spacebar to select it, and you should hear "Voice" to let you know you currently have "Voice" selected in the submenu, but can still press up and down to hear the other options before selecting one. You can go back a level in the menu at any time with the X key. When you get to a specific setting, there are a few entries like "Change" and "Get Current Value" and "Reset to Default Value," so you'll want to select "Change" (the first menu entry you encounter) and then use your up and down arrow keys to adjust this and then press space to save the value.
So on a brand new game, changing the voice volume to maximum would look like this: p, space, down, space, space, space, up, up, space, p. Just in case the TTS voice is so low that you can't even hear it to navigate the menus.
Here are the settings I'd suggest adjusting:
Settings > Volumes > Voice Volume Settings > Volumes > Music > Music Master Volume Settings > Volumes > Sounds > Sound Effects Master Volume
Turn the Voice Volume up to max (10), and turn the others down to a level you're comfortable with.
And you're right, when you get to the Dojo, the first button Chili asks you to use is R. If you go too long without hitting the correct button, Chili will interrupt to remind you what you're supposed to be doing. This is the format for the rest of that Divining Rod tutorial: he will explain a concept, and then test to make sure you perform it, but if you take too long (10 seconds, I think?) he will interrupt to remind you again of exactly what he asked you to do.
Good luck, and we hope you give the game another shot. Let us know if you have more trouble or can't find a good volume mix so you can hear TTS, and you can always hop in the Discord to chat faster!