Do you need to contribute additional money to a traditional IRA in order for it to be tax deductible, or can the regular deduction from your paycheck be deducted?

[VolvoGirl]

The deduction from your paycheck is probably for a 401K not a IRA.  Only enter it from your W2, nowhere else.  It is not a IRA contribution.  You contribute to a IRA outside of work.  

[Opus 17]

An IRA is a completely different kind of account, controlled by different regulations and laws than a workplace "qualified" retirement plan, even though their purpose is similar.  (There are several different kinds of qualified workplace plans with different numbers like 401k, 403b, 401a, 457, and so on).

If you participate in a workplace plan, you might also be allowed to make tax deductible contributions to an IRA, depending on your income.  But you would have to open the IRA with your own bank, brokerage or investment house, after reviewing your eligibility. https://www.irs.gov/retirement-plans/ira-deduction-limits

In turbotax, any information needed about your workplace plan is already on your W-2.  Don't enter it again.  Only separately enter contributions you made with your after-tax, out of pocket money into a private IRA.