setting/removing featured image on specific posts

If the above cannot be done, how can I set the width of post main image for each post individually?

If I understand correctly, to remove the WP cake you’d need to add to CustomCSS or Child Theme style.css:

img.wp-image-1663 {
    display: none !important;
}

To get that, I rt-click on the image and select Inspect Element (Q). This brings up the Inspector tool and I can see the HTML being generated.

Additionally, if you look at the -body- tag towards the top you’ll see postid-1654 which is unique to this post. So you could use:

.postid-1654 img {
    display: none !important;
}

Only use the !important if needed.

10X rdellconsulting,

That is the one solution I was afraid someone will suggest because it is absolutely tailor made for each post.
If there is no other solution – I’ll do it.

I’m still trying to figure out a more generic solution, maybe with custom fields?

Following @rdellcunsulting advice, I did this :

}
.postid-1654 .tc-thumbnail {
    display: none !important;
}

The result is exactly as I wanted, now I’m looking for a really general solution, so I will not have to add CSS rules for each post that I need to “hide” the main image.
https://www.glezer.co.il/2015/05/%D7%90%D7%AA%D7%A8-%D7%94%D7%95%D7%95%D7%A8%D7%93%D7%A4%D7%A8%D7%A1-%D7%A9%D7%9C%D7%99-%D7%91%D7%9F-%D7%A9%D7%A0%D7%AA%D7%99%D7%99%D7%9D/

Any ideas?