can i verify installed game

Yes, it's the same
This is why I asked "transferred files from a different device with the Xbox app"

Unfortunately nope, you need to redownload the game

no i mean i got forza 5 files from my friend and i want to verify it in xbox app without download it again like we did in steam

Hi and thanks for reaching Microsoft Xbox gamer's community. My name is Josef.
I'm an Independent Advisor and a Microsoft Xbox user like you.

Hope you're doing great today MOBAIOMY

Are you referring to verify pasted or transferred files from a different device with the Xbox app or similar?

If yes, nope. That's not possible because each PC has like an unique ID / license for every game ijetaooee using the Xbox app

If you're using the same Xbox Live account that purchase the games, the games will be available to install in "my game and app" on the "ready to install" section.

You can verify your purchases here:

https://account.microsoft.com/billing/orders/

Regards!

If you install a game from disc, you still need the disc in the drive in order to play the game. It's so it can verify you actually own the game.