You can use the FloatingImageBlock class to create an image behind text/table. Please see the snippet below and let us know if you have any other questions.
FloatingImageBlock imageBlock =
// Change image sizes
imageBlock.ImageInline.Width = 630;
imageBlock.ImageInline.Height = 200;
imageBlock.WrappingStyle = WrappingStyle.BehindText;
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.