In VV1, it's not the techs that allow burial, it's solving a puzzle. And the same is true for watering the flowers. Water from the well won't do anything for them. If you watch the messages that the game is giving you when you try things, it should help you a lot.
The "fishing milestone" you are referring to is also a puzzle that has nothing to do with the fishing that your villagers are doing.
If you're very frustrated, you could always look at our
VV1 Guide Section for help.
