Using Force to push player character along a sloped surface (player needs to be able to slide up and down the slope and generate speed)

Somehow I still do not understand how this is supposed to work. Can we see a sketch? A rough diagram with some wonky arrows?

At this point I feel like you want to constraint the plane of movement of the player somehow. There’s a lot of nuance that can be built into this, ofc, depending on how much control is needed. Or perhaps the end result should be closer to:

But the player can wiggle around a wee bit?