Although, you cannot convert Excel spreadsheets to Word documents directly via Aspose.Cells APIs. FYI, Aspose.Cells is a spreadsheet management library that manages MS Excel file formats only. We have another component i.e., Aspose.Words that manages or merges MS word documents. But, I think for your specific requirements, you have to use two Aspose APIs with two steps, that are; Aspose.Cells & Aspose.Pdf to achieve your goal. You will use Aspose.Cells APIs that allows you to convert the spreadsheet formats (XLS/XLSX, etc.) to PDF format. Then you will use Aspose.Pdf APIs which allows you to convert PDF to Word document for your needs.
I am working as Support developer/ Evangelist at Aspose.