NathSM wrote:What should i do? I just wanna play a game
Don't run Virtualbox for this project. Dual-boot your PC with Windows 7 and 10. Your computer isn't strong enough to run Windows 7 and 10 and Virtualbox and a decent game all at the same time, as Mpack says. And games don't perform well in a virtual machine of any hypervisor, they run much better on the bare metal.
For your case, Windows 10 should be installed on a separate disk drive, so you can reboot and choose which operating system you want. Then install the game on 10.
Or since you think you could run the game on 7, just run it on the 7 you have installed now.