If she had health insurance for all of last year, and it was not a Marketplace plan, then all you need to do is the following:

 In your open Federal return, choose the tab Health Insurance.  Then take the following steps:

• On the page Did you all have health insurance coverage in 2018? choose the radio button next to the option  We all had health insurance coverage all year and Continue
• When you get to the page Was anyone covered by any of these plans in 2018? answer No. 

If your wife had a Marketplace plan for 2018, then answer Yes and TurboTax will allow you to enter her 1095-A.