ExceltoWord is a Excel Add-in that assists the population of Word templates with Excel data. The original code was first developed by David Miller in 2012. You can see the original post here: https://www.experts-exchange.com/articles/8933/How-to-quickly-and-accurately-populate-Word-documents-with-Excel-data-charts-and-images-including-Automated-Bookmark-generation.html
I then modified the code (specificaly the 'ExcelBookmarkHandling' module) to create a link between word and the excel spreadsheet. In that way, any time you update a value in the spreadsheet, the form or the document you are trying to populate, will also update.
This code is ideal for people who needs to fill out forms or repetative letters in a weekly basis.
For clear instructions in how to use the code, please visit David Miller's post on https://www.experts-exchange.com/articles/8933/How-to-quickly-and-accurately-populate-Word-documents-with-Excel-data-charts-and-images-including-Automated-Bookmark-generation.html