I tried the withdrawal, but it need "Destination Tag" for the Bnb withdrawal (Mandatory) ? What is that ? When I try to input "Bitget", it said "Withdraw unsuccessful. Please check your withdraw address & amount."
The destination tag or memo consists of several characters (letters and numbers) and is an identifiable piece of information for an exchange to know whose account to credit with an incoming deposit. You usually don't need this if you are depositing funds to your own non-custodial wallet. But if you are depositing to a different exchange (in this case Bitget), the exchange probably uses the same receiving address for incoming BNB deposits from some or all of its players. The destination tag is how the exchange identifies where the coins are supposed to go.