I removed the Apple Health app from my iPhone Home Screen. It is still on my phone, but how do I add it back to my Home Screen?

Use App Library to search the Health app, see -> Organize the Home Screen and App Library on your iPhone

Organize the Home Screen and App Library on your iPhone - Apple Support           

• If you have find the app, tap & hold on the app, then drag to the Home screen & drop it.

With pleasure to be able to help you.

Thank you for your feedback and you're welcome.