You can attach files to a chat so the AI can read them.
Attaching a file
1. Open the chat and click the + button below the text box.
2. Pick your file. You can also drag one onto the chat box, or paste an image straight from your clipboard.
3. Say what you want done with it. "Mark this against the rubric" or "where did I go wrong here?" gets a far better answer than sending the file on its own.
From your phone
The attachment menu also offers Upload from phone, which shows a QR code. Scan it, take the photo on your phone, and it lands in the chat on your computer. Handy for photographing handwritten working.