I want to paint my bed room Richard Petty Blue. Sorry if i sould like a fool btw i know nothing about paint 😂. What do i need to know to go to like homedepo and buy that color

I would open Photoshop/paint, sample the exact shade, print it and take that sheet to compare with the colour cards they have there

yes, just find a sample of the color (like this picture) and bring it to home depot, they can mix paints to get the right color.