You usually get a set amount of money to bet when you deposit and that money can't be redeemable for cash. For example, if you bet the bonusR$5 and lose, that money is gone. If you betR$5 and profit anotherR$5, you'll be upR$5 in real money.
Yes, you can use several options to make deposits and cashouts. Depending on what is available to you, you can use the options that Sportingbet accepts. You can always choose a different option when you need to.