Hi Nicholas,
Yes you can.
My posts keep getting deleted for some reason.
At first I thought it was the Amazon link but when I got rid of it, the same thing happened, so I am truly down to as basic info as possible, unfortunately.
I have been using 3 external monitors to my Surfaces since Surface Book 1, all at 2560x1600.
I connect two via the monitor ports and the third via a USB to DisplayPort adapter (you can search for that on Amazon). I use the adapter because it is the only way to get my third monitor working at the same max resolution as the other two. Without the adapter, it still works, but must be at a lower resolution.
Today, I have a Surface Laptop Studio and my three external monitors are at 3840x2160 and I'm using the same setup with the DisplayPort adapter.
Hope that helps!