Can I deposit/withdraw dollars to/withdraw from my account?

You cannot deposit fiat currencies [Dollar (USD), Euro, etc.] other than Turkish Lira to Arbitex.

The USDT you see when depositing is called Stable Coin and is traded as a cryptocurrency. When you make a USDT deposit, you are depositing a dollar-indexed cryptocurrency.

Deposits in dollars (USD) cannot be made directly to Arbitex accounts, but you can make deposits in dollar-indexed cryptocurrencies. Detailed information about cryptocurrency deposits can be found in the category "Cryptocurrency deposits > How can I make a cryptocurrency deposit?".