ETH staking on Binance

Hi. I want to stake my ETH on Binance. I have read that you get a BETH token in replacement. But how does it work? Does it mean I can basically stake ETH and still have these BETH tokens that I can technically sell?

What about capital gains? If I start staking this ETH and I have already made profit for holding it, will staking (and the switch to BETH) make this taxable aka capital gains tax?