bitcoin2cash, when I click on 'FAQ' or 'About Us' it doesn't work.
There's no content for those pages yet. I'm still waiting to see what the FAQ are.
To buy bitcoins you place a bid. In the amount you put how many bitcoins you want to buy and the price you put what you are willing to pay per BTC. So to spend 5 USD you could buy 5 BTC at 1.00 each or 50 at 0.10 each or whatever.
Also, there aren't any error messages yet so if you do something wrong it will just redirect you to the account page instead of explaining what you did wrong. I'm working on that currently.