TurboTax automatically claims this amount for you if you are eligible.
It's calculated based on you and your spouse/partner's combined net income, so it's important to enter your spouse/partner's income into your return, whether you're preparing your returns together in TurboTax or not.
If you immigrated to or emigrated from Canada during the tax year, your claim is prorated for the time you were a resident of Canada. For details, see Newcomers to Canada.