Can I come back to complete my taxes to add Gambling losses once I get statements from casino? Can I get a filing Extention since I am awaiting these statements?

[MonikaK1]

If you are waiting for information returns and still expect to receive them, you can choose to file an extension.

However, to ensure that the extension is considered valid, finish (without filing) your returns in TurboTax including your best estimate of the gambling income, and if there is tax due, pay the tax with the extension. Do the same for your State return if applicable.

See this tax tips article for more information from TurboTax regarding extensions.