If you are filing jointly, you will only file one income tax return. So if you file using TurboTax, so will your spouse.
A joint tax return means that as a legally married couple, you are filing ONE tax return that has all of the information for both of you on the same tax return. Your personal information, your income, your dependents, your credits and deductions--everything. The refund will come in both of your names.
To begin a new joint return on TurboTax:
You will not be able to merge two previous TT account to start your new joint return. You can transfer ONE of your 2018 returns into a new return, so choose the most complicated one. The other spouse’s information needs to be entered manually.
When you enter your own information in Personal Info, you have to answer the question "Were you married?" If you click the button for Married, then a drop down will appear that asks, "Do you want to file this return together with your spouse?" Then you choose yes to file a joint return. You would then enter your spouse's information into Personal Info. Whenever you are entering income information there should then be a spot for you and for your spouse's income information.