One PDF is easier to email, print and keep than a dozen loose photos, and it keeps them in the order you meant: photographed receipts, scanned forms, screenshots for a report.
How to turn images into a PDF
Open Images to PDF and add your photos: JPG, PNG, WebP or iPhone HEIC, as many as you like.
Drag them into order, and turn any that are sideways.
Pick the page size (A4, Letter, or the same as each photo), the orientation and the margins.
Make the PDF and download it.
Getting a clean result
Set Margins to None to fill the page with the photo.
Same as photo gives each page the shape of its picture, with nothing cropped.
For photos of paper documents, Scan to PDF straightens the page and cleans up shadows first.