realfavicongenerator | Generate favicon for all major platforms | BPM library

I'm wondering how to change the default favicon on the browser tab using a nano react app and displaying it on localhost. I've already tried the whole process using https://realfavicongenerator.net/ but I don't have the static nor the public folder since it's a nano project... I'm not sure it's possible either

I want to add a Facebook Open Graph image to my website, and since I know there could be multiple layouts, I've chosen the square one.

The problem is that if I simply add a meta tag like this:

Facebook Debug Tool and other tag checkers such as realfavicongenerator.net display a 1.91/1 ratio image (my 1/1 image cropped by an 48%).

On the other hand, when I crawl other websites such as stackoverflow.com, both Facebook and RealFaviconGenerator display a square image (Stack Overflow has a 318x318 Open Graph image) instead of a rectangular one.

But in Stack Overflow source code (ctrl+U) there's nothing like og:square or og:ratio (there aren't even og:width and og:height).

So, how can I tell Facebook to use a square ratio for my Open Graph image? I found less than nothing inside the official documentation.

Setting up different meta tags as described here only creates undesired conflicts.

This is my website main page if you want to check the source code.

UPDATE: After Simone's answer I tried every possible pixel size, and I found out that the maximum allowed size for an og:image to be considered a square by Facebook is 445x445 pixels.

A 446x446 image is treated by Facebook as a wide one (information never mentioned inside the documentation).

Hope it helps.