Where can I see all the images I've uploaded and how much storage I've used?

Go to Settings → Web Settings → Media Settings. It is your store's whole media library.

• The cards at the top show Capacity (storage used against your limit), Images, Videos and 3D Models. Storage used shows the same as a bar.
• Filter by All, Images, Videos, 3D Models, Fonts or Documents, or by folder.
• To upload, pick a folder in Upload to folder (or New folder…) and click Upload media.
• Click a file to see its size and URL (Copy). You can add Alt text, Title, Caption and Description, then click Save details.
• Delete removes a file permanently. Check that no product or page still uses it first.