What are the trading fees?
You will only pay normal trade transaction fees as with the exchange:
0.1% for spot and 0.04 for futures.
If you mark "Use BNB for Fee's" on Binance, you will only pay 0.075% and not 0.1%. Then of course you will need to have some BNB on the Exchange to pay for it.
If you use KuCoin exchange, you can pay Fees via KCS to have 20% off: https://kucoin.zendesk.com/hc/en-us/articles/360037007974-Pay-Fees-via-KCS-Enjoy-20-Off