Do I need to pay tax for the amount which I have in the bank? If so, what's the tax percentage for a savings account and a current account?
In India, assuming that you have already paid relevant [Income/Capital gains] tax and then deposited the funds into your Bank [Savings or Current] Account; there is NO INCOME tax payable for amount.
Any interest earned on this amount is taxable as per Income Tax rules and would be taxed at your income slabs.
Wealth Tax is exempt from funds in your Savings Account. I am not sure about the funds into Current Account of individual, beyond a limit they may get counted and become part of Wealth Tax. More details here http://timesofindia.indiatimes.com/business/personal-finance/Do-you-have-to-pay-wealth-tax/articleshow/21444111.cms
Not for the amount in the accounts but for the interest you earn per year is taxable. But the sum of your all taxable incomes is under the limit, then you dont need to pay any income tax. The limit is available at wiki here
But you should intimate your bank not to deduct TDS (Tax Deducted at Source) by submitting Form 15G/15H (which will be normally available in Bank itself), provided your total interest income for the year will not fall within overall taxable limits.
You may calculate your income tax amount at Official website at here