Put it on the Home Screen: in Safari tap Share → "Add to Home Screen". It then opens full-screen with no browser bar.

Lock the iPad into the game: Settings → Accessibility → Guided Access → on. Then triple-click the top button while the game is open.

No sound? Press the volume-up button on the iPad's edge while the game is open, then tap the paw. Sound can only start after a tap.

To reopen this panel, hold a finger on the top-left corner for 2 seconds.