Please how do I get my wallet ID on my phone?

You have the Wallet app on your iPhone.

Try this: Use App Library to search Wallet app, see this Apple article:

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.

do you mean the app, or your state ID?