Can I do two income tax returns on my account If so ,How

Please read this TurboTax Help topic on how to start a new tax return for another person.

If you are using TurboTax Online, you cannot prepare and file a tax return for another person using an existing TurboTax account. You'll need to create a new account for yourself, distinct from the account you used to file your son's return last year.

If you are using TurboTax Desktop, you can start a new return for yourself by clicking on Start a new return on the Welcome page of TurboTax.

For an online account you can only do one return. To do another online return you will need to create a separate account.