We don't have any experience yet with First-BTC, however, it was a verified exchanger on BestChange. Visit BestChange to confirm if it's still verified.
At the current time our best crypto exchange for Brazil is:
Binance. If you are seeking for an alternative to First-BTC you should start there. To see every one of the top rate crypto exchanges available for you, see our list:
Brazil Crypto Exchange. Should you wish to visit First-BTC anyway, their website is
www.first-btc.com.