What should I do with the possessions (cars, furniture, computer, internet) that I bought with bribe money? Should I give charity from my lawful money on behalf of the owners of the money, or should I sell the cars and spend their money? What is the ruling on using the computer that I bought with bribe money, knowing that I have repented?

You must strive to estimate the wealth you took as a bribe and disburse it to its rightful owner, even if it means selling your possessions. If the price obtained is insufficient, the remainder stays as a debt upon you. If you are able to repay without selling your possessions, then you are not obligated to do so. If you know the owners of the wealth and they forgive you, your responsibility is cleared.