If I buy this will I be able to play the game on Windows 10
Forza Horizon 3 Shop Link
P.s. I don’t have an xbox one
That link goes nowhere for me, but I got around it and I certainly wouldn’t trust it. It looks very dodgy to me.
But you DO NOT have to buy anything for the game, except the game itself and certainly not an account. As long as you have an update Win 10, a machine with a set of specs that will run the game and an MS/Xbox account then you should be good to go. When I say ‘an MS/Xbox account’, I mean the completely free ones. If you’ve signed in to the Win 10 store then you more than likely have one already. If not go to the store and sign up, or use the Microsoft store on their site. Once you’re in you should be able to buy the game through one of those two outlets, or you can go to a third party (Amazon, Gamestop etc) depending on where you live and get a code to redeem.
Also, you DO NOT need an Xbox Live subscription of any kind to play on Windows 10. You don’t need an X1 either, you can download just the Win 10 version if you don’t have a console.
Does that clear it up for you? 
Yeap thanks for the quick response sir !!