I believe you mean how do you enter IRA contributions for more than one taxpayer or to more that one financial institution?
If so, you combine all of the contributions by type and individual (traditional versus ROTH IRA contributions). Then you follow these steps to input your contributions in TurboTax:
1. Navigate to the Deductions and Credits section of TurboTax, in the Federal section of the program
2. Find Retirement and Investments
3. Choose Traditional and Roth IRA Contributions
4. On the screen that says Traditional IRA and Roth IRA indicate what type of contributions was made and by who
5. Work through that section to enter how much was contributed in total to your IRA's