I have Photoshop 2021 on Mac. In this version, I want to open a sequence of images, but when I open it, I have a question mark on the layer and I can't do anything with the sequence. In the sequence, only the very first image opens, all the others seem to not even be loaded
Did you get this file from somewhere or did you create it yourself? The question mark usually means that there are some images in the sequence which are linked to original images outside of Photoshop. So if you don't have the original images with you OR if you've moved the original images from their location, then the opened file in Photoshop will show those linked images as missing by showing a question mark symbol.