You can scan and sign documents with an iPad and Apple Pencil using iOS 14.
Open Notes and select a note or create a new one.
Tap the Camera button, then tap Scan Documents.
Place your document in view of the camera.
If your device is in Auto mode, your document will automatically scan. If you need to manually capture a scan, tap the Shutter button or one of the Volume buttons. Then drag the corners to adjust the scan to fit the page, then tap Keep Scan.
Tap Save or add additional scans to the document.
(This how-to is based on my experiences and info on Apple’s support pages — where the images sometimes come from.)