If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
Swim above river to arrive at the slope of the river. Pick up the bottles in the way that will give you score jumping to take them. The beaver will help you to jump cascades. Use the right cursor to move against the river. You must press it repeatedly to advance. Jump on the end of the tail of the beaver to jump to the other side of the cascade.
Arrow key right- To move.
Space bar- To jump.