Thanks for your inquiry.
Unfortunately, Aspose.Words does not provide API to move the cursor to a location using distance from margin. You can move the cursor to any node in the document and insert content. Please read about Aspose.Words document object model from here:
Aspose.Words Document Object Model
Please share your input document and provide detail where you want to move the cursor in it. We will then provide you more information about your query along with code.