I'm not sure if bitpanda is legit since I personally haven't tried using it, but the fees would be from the transaction fees since you're going to transfer bitcoin from your bitpanda wallet to your binance wallet. Withdrawal fees differ from exchange to exchange so better look it up yourself as I personally don't use bitpanda.
Binance charges a 0.001 withdrawal fee, so expect other exchanges to have a withdrawal fee of something close to that amount too.