Short answer
HubSpot's KB: from the forms index, export data or clone, unpublish or delete forms (Edit forms permission). Customize columns and save views. Comparing forms needs Marketing Hub Professional or Enterprise.
1. In HubSpot
The relevant screen in my demo portal.

2. Worth knowing
Unpublish rather than delete if the form still has useful submissions.
3. Related
Unpublishing a form and exporting submissions.