Your English is much better than anything I would produce in a different language.
See
Repeating Data (Populating Multiple Like Fields).
There are many ways to do what you want. That page has all that I know about.
Probably the simplest method is to use Insert > Quick Parts > Document Property. The page I linked explains how to use this. It is a long page. Search the page for "document property." With this method, a change made to any property changes it for all other instances of that property.