Can I restore my wallet?

How can I restore my wallet?

What do you mean? Set Wallet back to Home screen?

If so 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 Wallet app, tap & hold on the app, then drag to the Home screen & drop it.