Need to reset Apple ID password

This iPad had my Apple ID on it until I forgot the passcode and had to to a reset. On doing the reset, it went back to the initial Apple ID we used for set up which is my husband’s ID. Unfortunately we can’t remember the password and would like to reset it. I have been unable to reset the password using my phone. I can’t seem to be able to log out of find my iPhone and I can’t download apple support. It’s not available in my App Store. Don’t know what to do. The iPad is connected to my find my iPhone pls advice.