I started a business in 2016 as an S Corp out of my home. I believe I need to file a 1120 form. Can you direct me to where I can do that in Turbo Tax?

If you are new to corporations, I REALLY recommend going to a tax professional for AT LEAST the first year.  Doing things wrong can easily cost you thousands of dollars.

For example, unless you filed a corporate extension, the tax return is now late (it was due March 15th) and it owes a late-filing penalty of $195 per shareholder, per month that it is late.

If the corporation was profitable and you took money from the corporation for personal purposes, it is REQUIRED that you be on payroll (with the quarterly employer forms, unemployment, W-2/W-3, and State requirements).  If you have not done that, there are late penalties (and interest) for those as well.

A tax professional can help you navigate the requirements.

To file a S-corporation Form 1120-S tax return, you will need to separately purchase the TurboTax Business edition to file your taxes.  

TurboTax Business is a separate TurboTax product line for customers to file S Corp, C Corp, partnerships, estates, trusts and multi-member LLC.  It is not part of the TurboTax personal taxes editions ( Free edition/ Basic, Deluxe, Premier and Home & Business)

To purchase TurboTax Business edition, see

https://turbotax.intuit.com/small-business-taxes/