Dot product help

I want to tell if the player is looking left of a position or part or right of it. The trouble is I don’t have a lookvector for that position. I only have the lookvector of the player. How can I find the dot product between them to tell if I am looking left or right of the position?

Use cross product as it tells you the directionality of a vector.

Specifically this function made by @sleitnick is really awesome, angle between signed.

Also you can find the vector towards that part position from the humanoids position using the common formula:

Part.position- humanoid root part.Position