The stimulus payment issued in 2020, EIP1 and EIP2, are no longer available since it is beyond the 3 years from the due date of the tax return.
The stimulus payment for 2021 is available if you were eligible for payment in 2021. If you were being claimed as a dependent on a 2021 tax return you are not eligible.
If you filed a 2021 return then you will have to amend the return for the Recovery Rebate Credit. An amended return can only be printed and mailed. If will take the IRS 16 weeks or longer to process the amended return.
See this TurboTax support FAQ for amending a prior year tax return - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-a...
If you never filed a 2021 tax return -
To complete and file a 2021 tax return using TurboTax you would need to purchase, download and install on a personal computer one of the 2021 desktop editions from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
A 2021 tax return can only be printed and mailed, it cannot be e-filed using TurboTax.
Before you file anything make sure that the IRS has not already sent the stimulus payment of $1,400 to you back in 2021. Go to this IRS website and open your Tax Account - https://www.irs.gov/payments/online-account-for-individuals
