To scan a document on your iPhone, you can use the built-in Notes app by following these steps:

1. Open the Notes app and either select an existing note or create a new one.
2. Tap the camera icon within the note, then choose "Scan Documents."
3. Position your document so it appears in the camera view. If your iPhone is in Auto mode, it will automatically scan the document. Otherwise, tap the shutter button or press a volume button to capture the scan.
4. Adjust the corners of the scan to fit the page as needed, then tap "Keep Scan."
5. You can add additional pages by repeating the scanning process or tap "Save" when done.

After scanning, you can save, share, or export the document as a PDF directly from the Notes app

. Alternatively, you can scan documents using the Files app by tapping the three-dot menu and selecting "Scan Documents," following a similar process

. This method provides a quick and convenient way to digitize paperwork without needing additional apps or hardware.