For any changes with retirement, you nearly always receive a form 1099-R. Enter the form and then answer the questions that follow carefully. This is how you tell the software what occurred.
A Roth is typically funded with after tax dollars so if you moved it to another Roth account, there would be no taxable implications. It's important to keep track of your contributions (before and after tax) and distributions carefully because the retirement companies do not track this information for you.
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