Follow these instructions to install Windows 8.1 from a USB drive using a new SSD.
Follow these instructions to install Windows 8.1 from a USB drive using a new SSD.
It depends on your setup to ensure the necessary drivers are available. Sometimes you need to download them from external storage before installing a new system, especially when using Wi-Fi for downloads.
It seems you might need to press a specific key to access the boot menu, since some systems don’t boot directly from the USB. You could configure the SSD as the boot device and then navigate through the menu.