my daughter turns 13 last week, she lives with me since 6 yo, now she wants to go live with her dad, change schoo, but her dad only has one bedroom condo, can my daughter just pack & go? since she turns 13?
Assuming that you have court-ordered custody, no she cannot. Once she reaches 16, she may petition the court for a change in custody and the court would be required to consider her wishes.
If there is no custody order, there would be no legal recourse from stopping her.