You can copy an artboard in Illustrator using shortcuts, a panel option, or a tool. You probably already tried Command/Control + C, what went wrong?
3 Ways to Change Artboard Size in Adobe Illustrator - wikiHow
3 Ways to Change Artboard Size in Adobe Illustrator - wikiHow
How to Duplicate an Artboard in Illustrator
Working With Artboards in Photoshop and Illustrator
How to add a border to an artboard in Illustrator - Quora
How to Create a Logo in Illustrator - Unlimited Graphic Design Service
How to Duplicate an Artboard in Adobe Illustrator - Bittbox
How to Add Artboards in Illustrator
Manage artboards