There is a standard image size for product descriptions. The maximum width is 1000px and the maximum height is 5000px. You can see this when you upload pictures.
Although the maximum width is 1000px, it is not recommended that you make it so wide. Generally, a width of about 800px is more appropriate. The picture is too large and it is not conducive to seeing the entire picture at a glance. If you set the image width size to 800px, it is best for all images to be the same size. Otherwise, the width of one picture is 800px and the width of the other is 500px, which is very uncoordinated and will give buyers a very unprofessional feeling, making it difficult for buyers to trust you. So after a certain width is determined, all images must use the same width.