Pixel point selection and draw line on the picture with Javascript

I need X-Y position selector.

I want draw line (SVG or Canvas) and select pixel.

"** Firstly look at the sample video file I uploaded. **"

I have a 4k image and I want to select a certain coordinate from this image.
But I also want to be able to add lines wherever I want. Exp: to identify junction points

I will share sample site information later.

Elements used in the example:
-> Raphael.js