To copy a pre-existing email campaign into a new one:
Navigate to CAMPAIGNS via the main menu.
Click on the 3 dots on the right hand side of the campaign whose template you wish to copy.
Select the Copy Campaign option from the pop-up.
Fill in new campaign details such as New Campaign Name, New Campaign Description etc. You will also have an option to attach the contacts associated with the campaign you are copying by ticking Copy Campaign Contacts into New Campaign.
Go to the newly created campaign's Campaign Details page and update the settings as required. You can of course edit the content in the new draft campaign as well.
NB: if you are not seeing the 'Copy Campaign' option in the drop down, that's because the campaign was created in a version of the Enudge editor that is no longer supported. Instead, you will need to create a new email campaign.