SmartTRADE is a fast, secure, no-fee* way to buy, sell, and swap or convert cryptocurrencies.
After logging into your SmartPORTAL, click on the SmartTRADE link at the top.
You will see tabs for Buy, Sell, or Convert.
Check out this article to see which cryptos you can buy and sell for fiat, and which trade pairs SmartFi supports. 
*SmartFi does not add fees for transactions in SmartCYCLE. Normal network / gas fees apply.