Coordinates of points and entering coordinates as edge starting point

[MikeWayzovski]

@ChrisJ7903

Is there a way in SketchUp to reveal the precise 3D coordinates (x,y,z) of an existing point, whether it is a line end, an intersection point, or the vertices of an object?

Select the label tool

and click on an endpoint/midpoint. Since version 2019, you can select the tapemeasuretool and hover over the points.

@ChrisJ7903

Similarly, is there a way to draw a line from (x1,y1,z1) to (x2,y2,z2) without drawing lots of guide lines first?

Why do you want to do that? Do you know all the vertices from memory?
If you want to do more ‘techsavy’ stuff, learn to place the drawing axis (rightclick on one of the axis and choose ‘move’) and to draw relatively and absolute.

https://help.sketchup.com/en/sketchup/introducing-drawing-basics-and-concepts