This is an advanced section of the Form Builder Tools menu. It is geared towards users who are integrating with other XForm-building tools like Formhub. If you are building your forms entirely in the App Builder, you should not ever need to use this section.
The name of your form in the actual XML of the form. This name is used on some reports on CommCareHQ. In most scenarios the mobile phone and CommCareHQ reports use the name you give the form in the App Builder instead.
The form ID is the question ID of the largest group in the form, which is there by default and contains all the questions in the form. When you create a form in the Form Builder, this group is always named "data". You'll notice when you refer to questions in a display condition, the syntax is always /data/question_id. This is because you are writing out the path to where the question is located in the form, and the question is always inside the "data" group.
Forms created in other tools often have a different form ID. This is fine. We warn against changing the Form ID here because it will not automatically change the Form ID in existing references in your logic conditions. If you change the Form ID, you must manually change any existing logic references.