You need to connect your nodes.
The white wire is the execution line, the coloured wires are data or data targets.
Blueprint nodes are context sensitive, you should always take advantage of this. Do not just plop them in the graph. Instead, drag a wire off AsDistanceMeasured’s blue pin, search for the text block and Get it. Do not Set here, you’re not replacing the widget, you’re obtaining the reference so you can adjust its embedded text.
SetText needs a target, too which is the text block on the left. Just connect them all:
The conversion from string to text (which widgets love) is automatic. Widgets can work directly with strings (when binding property) but in this very case it needs to be converted.
Oh, btw, it takes years to take it all in. I had questions just like yours 3 years ago but there was hardly anyone to answer them back then. So it was trial and error, mostly error.
Also, I’m completely unfamiliar with VR development, is the red beam a spline or a particle emitter?