You can download Zotero from here.
You will also need to download the add-on Zotero Connector for browsers like Chrome, Firefox and Opera. Then you will get an icon that lets you import references directly from internet to your Zotero library.
The icon in your browser will change according to the source displayed at the web page. It could look like a book (when you are looking at a book):
Or it could look like a sheet of paper when you are looking at a web page:
There are other icons as well, but all of them says "Save to Zotero" if you hoover them.
Please make sure that you have the Zotero toolbar in Word.