TurboTax automatically uses your standard deduction unless you enter enough itemized deductions to exceed your standard deduction or force itemizing because you are filing MFS. Look on line 8 of your Form 1040.
https://ttlc.intuit.com/questions/1901539-how-do-i-preview-my-turbotax-online-return-before-filing.
Your standard deduction lowers your taxable income. It is not a refund
2018 Standard Deductions:
Single $12,000 (+ $1600 65 or older)
Married Filing Separately $12,000 (+ $1300 65 or older)
Married Filing Jointly $24,000 (+ $1300 each spouse 65 or older)
Head of Household $18,000 (+ $1600 65 or older)
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