This guide explains how you can activate any skills.
Guide to Activate Different Skills
Open the menu (left hand A button), and go to the godstones section (second button at the bottom I believe).
It shows you all the different skills and how to activate them, but you should only be looking at the ones that have a godstone slotted.
Remember! Skills don’t always ‘equip’ when you unlock them. I had to manually turn on my Dash ability before the icon displayed on my UI and I was able to use it.