Ecommerce Site Duplication for makeover

I’m about to embark on a redesign of a current Ecomm Plus Site, but would prefer not to do the work on the live site until it is all approved by the client. What are the steps for a smooth transition?

Can I work on the CMS portions (store items) without affecting the current? Anything I should be aware of regarding the hosting? Can I publish a sample under for review?

The shopping cart is not handled by Webflow, but uses js scripts that reach out to another shopping cart.

Thanks for any help you can provide.