Yes, but an internet connection is required to download from the website. An alternative method could be to download it onto a flash drive from another computer connected to the internet and then install from the flash drive.
As long as your motherboard has an available PCIe slot and F_USB header, and your system is running Windows 10, it should work. Please ensure the adapter and F_USB cable (if using Bluetooth) are properly installed/connected.
Theoretically, yes. However, depending on your system configuration and specifications, it may impact the available PCIe lanes for your GPU and other PCIe peripherals (if applicable). We suggest consulting the user manual for your motherboard and CPU to determine how your system handles PCIe lanes.
Most modern motherboards will include an internal USB header. The most common nomenclature of this header is "F_USB"; however, it can be labeled differently depending on your motherboard manufacturer and model. If your motherboard does not have any USB headers whatsoever, then the Bluetooth feature will not function.