Finding Corresponding Points on two rectified images

edit

Hello,

i have 2 images and also the intrinsic camera parameter K.
I calculated the fundamental matrix F of both images and rectified the images using the homography.

Now i would like to implement that:

If i click on any point at the first image, the corresponding image point on the second image should be shown/selected. But how can i exactly calculate, which selected point from the first image belongs to which corresponding point on the second image?

I already know that x' F x = 0.

That's where i am now: imgur.com/a/qlYG5

EDIT:
I already did the feature detection and feature matching steps (e.g. to find out the fundamental matrix F).
Now i want to implement, that i can calculate the correspondence of ANY point on the first image to the point on the second image.