Project Web App is a web-based application that assists with managing projects, tasks, and workflows. In this site, the main components are the Quick Launch (left-hand links), ribbon (commands at the top), and the content display area (section below the ribbon).
Projects created in Project Web App can be either an Enterprise Project (editable in Project Web App) or SharePoint Tasks List (a project subsite with SharePoint features).
Note: to view the site, users will need to have a Project Online license assigned to them.
No, the PWA site and regular SharePoint site are separate site collections and their tasks/projects can’t be imported to the other. In https://project.microsoft.com/en-US, only PWA sites can be used to update the Project Online link.
Project files (created in https://project.microsoft.com/en-US/) and PWA Project files (created in PWA sites) can be displayed in a tab in a team. Members of the team must be given access to the project files and have Project Online license.
A tab with the project will be displayed.