If you need to enter your spouse's info, go to the Personal Info tab at the top of the page. Select Edit next to your filing status to change it to Married.
If you've already added your husband's personal info and need to enter his income, go to the Wages & Income tab. Select Add/Edit next to the area where you need to add income: W-2, 1099-MISC, etc.
From there, you can add your husband's income info.
If you have other forms you need to add, you can visit each section and enter them there. The sections are organized by the tabs at the top of the page: wages & income, deductions & credits, health insurance, etc.
I attached screenshots for reference.