The amount you pay towards your health Insurance premiums through work could be listed as a Medical Expense.
Medical expenses are only relevant if you Itemize Deductions rather that take the Standard Deduction.
If you know you will be taking the Standard Deduction, just ignore the request for your health Insurance payments.
If you are unsure if you will take Standard Deduction or Itemized Deductions, and want to enter your Health Insurance payments, look at your paystubs or ask your payroll department.
TurboTax does not know the amount unless you enter it.