Which good site can I trade bitcoin?
Binance will be a good choice because you don't have to fill KYC. But if you are no problem to fills KYC, then you can increase your level in binance, and you can also register in poloniex, and bittrex. I think kucoin will also a good site to trade bitcoin.
But before you deposit, make sure you already choose which exchanges you want to use for day trading and don't forget that you need to have basics skills in trading.