No. You should add your spouse's W-2 before you go to the credits and deductions section because the additional income is going to effect both the calculations and your eligibility with respect to tax benefits.
To enter another W-2 in Turbo Tax:
Log in to your account
click on "take me to my return"
click on "federal taxes" tab
click on the "income and expenses" tab
scroll down to the W-2 section, and click on start/revisit
choose "add another W-2