I received an amended W2 late from my employer and i have already filed. I need to file an extension to amend my return. Can this be done through Turbotax?

If you have already filed your tax return, you do not need to file an extension to file an amended return.  You just need to file the amended return, but it is not due today, April 15.

Keep in mind: You have 3 years from the date you filed your 2018 return (or 2 years after you paid the tax due, whichever is later) to file an amended return. Allow the IRS up to 16 weeks to process the amended return.

See below for steps to file an amended return in TurboTax:

https://ttlc.intuit.com/replies/7276605