Most photo problems are easier to prevent than to repair. The capture conditions matter long before the crop is opened in an editor.
Make the session easier before touching the editor
Prepare the room, background and camera before bringing the applicant into position. For a baby or an applicant who needs physical support, take several originals and choose later. For an accessibility situation, follow any authority-specific accommodation instructions rather than forcing an adult “standard pose.”
What to keep from the session
Save the original frames and note which image was used. That makes it possible to produce another required output later without reshooting the applicant under time pressure.
When in doubt, retake
If the source is badly blurred, distorted or poorly lit, another photograph is usually better than a stack of corrective filters. Identity images benefit from a clean capture more than from heavy editing.
Start from the receiving portal
If the application page gives pixel dimensions or a file-size cap, those instructions are more useful than a generic passport-photo chart. If it asks for a print, use the physical dimensions and print-quality guidance instead.
The final file should be built for the actual receiver.
The part worth saving
If another person will handle the upload, send the final file together with its intended destination. This avoids the common mistake of submitting the correct portrait in the wrong format.
Newborn Passport Photo Guide
Use an existing photograph or capture a new one, then prepare the image around the requirement instead of around a generic preset.