I'm sorry for you loss. So that I don't waste your time, did your mom pass in 2016? If she passed in 2017, then you don't need to concern yourself with estate taxes just yet. Also, are you the legally recognized/appointed administrator of the estate?

She passed on May 24, 2016.

2017

brother in 2016

SO I take it she has "assets" that were transferred into an estate that was created by whomever the estate administrator is. I further assume the estate administrator has already obtained an EIN for the estate too. So to file the 2016 estate return, you need TurboTax Business (Different from Home & Business). The estate is a completely separate entity that files it's own tax return, and the legally appointed/recognized estate administrator is responsible (legally) for that.
TurboTax Business is used for preparing corporate returns, as well as estate returns. It is not available as an online product, or for MAC computers. Windows computers only. You can purchase it at https://turbotax.intuit.com/small-business-taxes/