How to slide down a slope/hill/steep angle???

Development Programming & Scripting Blueprint
,
2

I’d imagine the answer lies here:

How does Walkable Floor Angle work? - Development / Programming & Scripting - Epic Developer Community Forums

Walkable Slope in Unreal Engine | Unreal Engine 5.2 Documentation | Epic Developer Community | Epic Developer Community

As for sliding down, after detecting the angle is too high, you can apply a physics force to the player to cause them to drop until the angle is no longer too high.