Health app missing

I don’t see it in the App Store either.

If it may still be on your iPhone, perhaps in a folder:

Use Search on your iPhone, iPad, or iPod touch - Apple Support

These methods have side effects which you may or may not like.

• Settings > General > Reset > Reset Home Screen Layout
• Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Might your iPhone be restricted? Check Settings > Screen Time.

Or might your iPhone be managed by an employer or educational institution?

Did the health app ever appear on this iPhone to your knowledge?

That’s great news. Glad it’s resolved.

Enjoy your iPhone.