You will need a BIOS upgrade for the motherboard to support a 7th gen processor. What motherboard do you have?
No other component will need upgrading. As for Windows still working, it will depend. It most likely would, unless you get unlucky. I would still back up all data, in case it doesn't work. But usually a CPU swap doesn't require a fresh install. Also link your Windows license to your Microsoft Account, so that you won't need to buy another product key in case a fresh install is required.