You now have an opportunity to attach your Binance trading account. To do that you need to already have a trading account on Binance. To attach an external account point to the Dashboard sign and choose Trading:
Scroll down and you will see an option to "Attach external account".
After choosing the option, you will see a form to fill in. To attach an external Binance account you need to have an API key and API secret without the trading rights. You can find an official Binance guide on how to create an API here.
After you click "Attach external account" button, you will see your Binance account in your Trading section.