I know the cross production is the vector which creates the up vector/ right angle of two vectors.
Not to familar with the dot product. Care to share knowledge?

Denis i took your feedback on what values needed to be calculated. Im not clear on how to create the variable which is multiplied to the original node. I was hoping you could elaborate a bit more to help me out. Thank you

fn GetVectorsAngle v1 v2 =
(
	theAngle = acos(dot (normalize v1) (normalize v2))
)

fn PlaceAlongVector pos:[0,0,0] vec:[0,0,1] offset:0 =
(
	pos + (normalize (vec)) * offset
)

fn GetCornerPoint posA:[0,0,0] posB:[0,0,0] =
(
	/* Find the length to create a right traingle */
	-- get angle difference between 2 vectors
	difVector = posA - posB-- vector between plane and ball
	objVector = pln.transform.row3 -- vector using normal of plane
	dist = distance posB posA
	calcAng = GetVectorsAngle difVector objVector

	-- calculate the length of side to create a right angle
	len = cos(calcAng) * dist
	-- place point which would create a rightAngle at the sphere
	cornerPos = PlaceAlongVector pos:posB vec:objVector offset:len
	cornerPos
)

/* Test Scene Setup */
clearlistener()
format "
"
delete objects
pln = plane width:5 length:5 pos:[0,10,10] wirecolor:yellow
rotate pln (angleaxis 30 [1,0,0])
s1 = sphere pos:[25,40,0] wirecolor:red radius:2
s2 = sphere pos:[32,18,7] wirecolor:green radius:1

center = pln.pos
normal = pln.transform.row3

-- calculate corner positions which are then used to calculate correct vectors 
p1 = GetCornerPoint posA:s1.pos posB:pln.pos
point pos:p1 size:2 wirecolor:(random yellow green)
p2 = GetCornerPoint posA:s2.pos posB:pln.pos
point pos:cornerPos size:2 wirecolor:(random yellow green)

-- angle between new vectors
vectorA = p1 - s1.pos
vectorB = p2 - s2.pos
ang = GetVectorsAngle vectorA vectorB -- ANGLE NEEDING TO ROTATE NODE
crs = cross vectorA vectorB -- AXIS TO ROTATE

I have this data but im not sure how to then use it to rotate the node correctly…

ang = GetVectorsAngle vectorA vectorB -- ANGLE NEEDING TO ROTATE NODE
crs = cross vectorA vectorB -- AXIS TO ROTATE