The spline shouldn’t be a part of the pawn, it should be a separate blueprint actor with just a spline component in it.
The DistanceAlongSpline variable I used is just a float I’ve added, you can call it anything you like. So just add a float variable, with a default value of 0. If you drag that into the graph, you’ll have the option to set and get it, which is all I am doing there.
The Plus node is just a node for addition of two floats, if you type “+” in the menu you will see “float+float”
If you drag off from MySpline there and type in Get World Location, does it come up?
Edit: Also, I just tried and I can’t drag the pawn into the scene either, but if you have it selected and right click in the map you can add it that way