1. How do I use RadTabStrip from CMS?
You can use built in control in Sitefinity CMS or create a custom user control and upload it to the toolbox section.
In some posts, I see Sitefinity giving examples of RadTabStrip and
RadMultipage which needs to placed in masterpage. I tried that method
but I cannot change tabs and view different page views. It defaults to
SelectedIndex="0" of RadMultiPage therefore not able to drag and drop
Most probably you are referring to page edit mode. You should add css and style RadPageView control to make all mulitapges accessible. You should add a CssClass and use display: block property. You could add your css class to ~/Sitefinity/Admin/Themes/Default/PageEditor.css and ~/Sitefinity/Admin/Themes/Default/PageEditorOverlay.css( for overlay mode)
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