Rocks contain lots of useful materials for crafting tools and furniture, so it is important to learn how to make the best use of them.
In order to hit a rock 8 times in a row, you’ll need to dig two holes at the correct position and position yourself diagonally to hit the rock with a shovel 8 times.
Here’s a video showing how it works:
And in order to destroy a rock, you’ll have to eat a fruit to gain stamina and hit the rock you want to destroy with a shovel. The rock will eventually respawn the next day at a different location.