How to transfer old ipad app to iPad Pro

How to transfer JUST ONE app game on old ipad to New iPad Pro

game app called ‘Smash Spin Rage’

I done backup from iPhone everything Apps iCloud to new iPad.

But still not the old iPad - but did the backup up to iCloud for now but thought myself doesn’t need to reset my new iPad which I already downloaded all from iPhone.

i have the game app on the old one but how to I transfer on the new iPad.

I searched Google for possibly download etc none is availability

not even on Apple store.. but yes on my purchase account in Apple.

just need help there…

those Apple tech wizards outta there may know something…

Regards

Paul