Installation:
- Go to the SharePoint Store from your SharePoint Online site or Microsoft Appsource.
 - Search for “Virto Gantt Chart” and click “Add” to install the app.
 
Configuration:
- Add the Virto Gantt Chart web part to your SharePoint page.
 - Configure the data source by linking your SharePoint lists to the Gantt chart.
 
Using the Gantt Chart:
- Adding Tasks: Click on the chart and enter task details.
 - Modifying Tasks: Use drag-and-drop to adjust durations, dependencies, and completion percentages.
 - Customization: Customize the chart’s appearance and timescale to fit your project needs.
 - Advanced Features: Manage multiple projects, export charts, and set user permissions.
 
For more detailed information about product setup and other details, please refer to the Virto Gantt App for SharePoint Online Documentation.