Klaus Frank on Nostr: You basically have to start with a generic gimp tutorial and thereby discover what ...

You basically have to start with a generic gimp tutorial and thereby discover what the terminology within gimp is so that you can google for it. Spoiler "Image" is not what you've currently selected but the entire project/file. So what you want to do is "Image > Crop to content" after you've clicked on "Layer > Transparency > Add Alpha Channel" just so that Gimp doesn't replace the shown transparency with a random color for no obvious reason (so a novice at least perceives it).