Pretty cool game idea! Reminds me of Re: Run by Dani (I'm assuming some inspiration was taken in the name and a bit of the gameplay).
Movement has some issues though, as a Unity dev I have a good feeling I know the fixes so I'll put them here:
So when you double jump in this game if you don't double jump instantly after the first jump the double jump does not go very high, this is most likely due to in the code you haven't set the rigidbody velocity back to 0 right before you jump. This would allow the double jump to reach full height no matter when you do it.
The bounciness and friction the player has is due to not having a proper physics material, you can create one within your assets folder, then set Dynamic Friction to 0, Static Friction to 0, Bounciness to 0, Friction Combine to minimum and Bounce Combine to minimum (these parameters may be different in older versions of Unity but just set everything you can to 0 basically).
So aside from that there's some neat levels in here, simple but nice enough layouts, wall running feels pretty good too! Good work!