Short answer
Add your images to a JPG to PDF tool, put them in order, choose the page size and make the PDF. Each image becomes one page. The free JPG to PDF converter on this site does it in your browser, so your documents are never uploaded, and it can make the file small enough to email.
Free tools for this
Put the pages in order
Add all the images at once, then move pages up or down until they are in the order you want. Turn any photo that came out sideways. Remove any page you do not need.
Pick the page size
Choose A4 for documents in India and most countries, or US Letter for the United States. Direction can follow each photo, so a wide photo gets a landscape page. For a scan that should fill the page, set the margin to none. Or choose a page the same size as each image.
Try it now: JPG to PDF Converter → · Image Compressor →
Keep the file small
Photos from a phone are large, and a PDF of ten of them can be too big to email or upload. Choose the Small file quality to shrink it a lot. Check the result is still readable, especially for text.
Keep it private
Documents like IDs and bills are sensitive. This converter builds the PDF in your browser. Nothing is sent to a server.
Text is not searchable
A PDF made from photos holds pictures, not text, so you cannot select or search the words. For that you need OCR, which turns the picture into text.