How do I save a SharePoint template?
When your page looks the way you want, click the down arrow next to Save at the top of the page, and click Save as template. Once you've saved your template, it will appear in the Templates pane under Saved on your site.
How do I copy a SharePoint online list?
If yes, you can create a new list, then go to Site settings > Content and structure logs under Site Administration > navigate to the list you would like to duplicate > select all items > click Actions > Copy to copy to the new list you just created.
How do I move a SharePoint list to another list?
Related Question How do I save a SharePoint online list as a template?
Does SharePoint save versions?
You can set SharePoint to save more versions, up to the system limit. For more info, see How does versioning work in a SharePoint list or library.
Does SharePoint keep version history?
Version History is turned on by default in SharePoint, but if you don't see the Version History command, it may be turned off. Depending on how your admin has set up SharePoint, you may be able to turn on list or library versioning.