Site using HTML and CSS (Flexbox & Grid)

Hello community, this was the first HTML and CSS application I made and I had a lot of difficulty with resizing the image correctly. The end result is not the way I wanted it, I did a lot of research but I couldn't fix certain resizing errors, if anyone can look at my code and take a guess I would be grateful.

Note: Resizing errors occur when you are changing from the largest screen to the smallest, in this process the image is not good.