Open the image you want to convert (JPG/PNG/etc.)
On Windows, right-click the image file → Print → select “Microsoft Print to PDF” → Print/Save
On macOS, open the image in Preview → File → Export as PDF → Save
On Android, open the image in Google Photos or Gallery → Share → Print → select “Save as PDF” → Save
On iPhone/iPad, open the image in Photos → Share → Print → pinch-out to preview PDF → Share/Save to Files
Use an online converter: upload the image → choose PDF → download the PDF
Use Microsoft Word: insert the image → right-click image → save as picture (optional) → File → Save As → PDF
Use Google Drive: upload the image → right-click → Open with Google Docs (if available) or use an online conversion step → download as PDF (if supported)