I have FIOS too, 75/35, like Bosamar.
No problems at all with the Surface Pro.
The 2-year old stock Verizon router, which is not an 'N' model, works fine with the SP and everything else I have pulling internet.
Have you done some overall trouble shooting?
First, can the Surface see your WiFi signal, but can't connect? Or can it not see it at all? I've had trouble connecting with other gear when I hide my SSID. Is it hidden? Or displayed? If hidden, try displaying it.
Then, if I were in your shoes, I'd take the Surface and try a bunch of other WiFi...Starbucks, McDonald's, even the hotspot on a smartphone, and see if you can get online using those connections.
Also, at home, I'd crank up other devices, like a laptop, and see whether they can get on using your FIOS WiFi.
These steps obviously meant to drill down and identify exactly what the problem is: your Surface; your network; or the way they communicate with each other.
If everything works perfectly, except for the Surface on your home network, let us know.
Good luck.