https://www.wpbeginner.com/wp-tutorials/automatically-remove-default-image-links-wordpress/
The above tutorial only helps in setting Image Links to NONE for adding new images.
But for older ones, it is not the solution. That is mentioned in the comments itself.
Since some blogs have more than 100 posts with 500 images, it is difficult to change each image link to NONE or whatever option we require.
There should be some automation to link all images to our requirement – NONE, MEDIA, ATTACHEMENT, CUSTOM URL etc.