The standard deduction is automatically entered on your return by TurboTax once
income is entered. Then, if you enter any itemized deductions, TurboTax
will compare the total to the standard deduction and determine which is
more favorable to your return.
Below are the 2018 standard deduction amounts:
https://ttlc.intuit.com/replies/4208574
Here is how you can change from the standard to itemized on your return:
https://ttlc.intuit.com/replies/3300919
