This new Gallery block looks very similar to the standard Image block, and it gives you a couple of main options:
Additionally, aside from the possibility of uploading images or picking them from the media library, you can drag and drop multiple images straight from your desktop. WordPress will immediately start turning them into a gallery. For this example, if you want to pick the images from the media library, just click on the Media Library button. You'll see a panel that should be familiar at this point. In there, just click on the images that you want to have included in the gallery. As an example, I've selected ...
