Windows allows you to convert any image file with JPG, JPEG, PNG format to PDF without installing any third-party software via Windows Photos App.

To convert a JPG file to a PDF file, simply change the file format on your computer's default photo-viewing app.

In the Preview app, for example, it's possible to create a single multi-page PDF document out of several separate image files.

Step 2: Drag your PDF files into the "Merge PDFs" box or click the "Select Files" button to add files.