Bootcamp Drivers Not Installing on Windows 10

I've successfully installed Windows 10 on an external drive. The only issue is that none of the drivers (for wifi, bluetooth, mouse, keyboard, etc) seem to have installed at all. I tried running the setup file in the bootcamp folder several times in hopes that it would install the missing drivers, but to no avail. I downloaded the Windows Support folder through bootcamp that contains the executable (.exe) files for the drivers and tried to manually install that way, and still didn't work. Without the drivers, there's no way to actually use bootcamp/Windows. Any ideas? Thank you!