We have a O365 SharePoint list with Nintex forms and workflow already in production and regularly used. I have a few requirement to update the form and workflows, what would be the best practice to incorporate the changes without affecting the users. The changes should be only available to users after testing the changes.

Should we have a development environment with a SharePoint list which mirrors the one in Prod with backing forms and workflows. Once the changes are tested in development, we should export the changes from development environment and import to the production instance

I would like to know what are the different approaches taken for development, deployment and maintenance