Hello, welcome to the dash datapack.
What it does: It teleports you 20 Blocks, in the direction your are looking in. You can also use it to gain height.
Dont worry, you cant dash into Blocks
After the Dash there is a 10 second cooldown.
There are also particles added, to make it look better.
You use it by pressing jump and sneak at the same time or sneak, while you are in the air