How do I edit the age range and gender for multiple ad sets at once?

On the Ad Sets tab, select the ad sets, open Bulk edits, click Edit Set, and choose Edit Age or Edit Gender. In the age window, set the minimum and maximum age and use Apply to all, or adjust ad set by ad set in the list. In the gender window, choose All, Men, or Women; you can also apply to all. Click Save changes and follow the progress in the window. Changing targeting can restart an ad set's learning phase in Meta, so avoid changing ad sets that already perform well too often.