Nighthawk x4s R7800 How do you Add VPN service to dropdown menu

[mel15]

I see where you can click on the VPN tab but the only service thats in the dropdown is purevpn and their reviews are terrible.  I already have Nordvpn and it works great.  They have instructions to flash your router but its a little to complicated for me.  I found the vpn tab so I thought there must be an easier way?

any help is appreciated!

[microchip8]

You can't add extra VPN services on stock firmware. Voxel's firmware and kamoj addon makes this possible

[mel15]

I'm sorry you are speaking a foreign language to me.  I am not sure what Voxel's firmware is? is that something I should download or change on my router.  I not actually sure what firmware I have now.  I just know to go and update it from time to time.