Zotero is a web based citation management system (free). You can install Zotero and the Zotero web browser Connector app to embed Zotero in your web browser. You can also install Zotero plugins in Word, Google Docs, and LibreOffice.
Download and install Zotero from the Zotero website.
Your web browser will detect a different version for each operating system: Windows, Mac or Linux. Apple app store has a Mac app available (2025). An Android version is coming soon, but not yet available (2025).