Add project members
Click on the arrow icon beside your project name, and select Edit members.
Next, click + Invite new member to invite people by entering their email addresses.
Change member’s permission
In the Members tab, click on the role of the member you want to change.
Remove project members
In the Members tab, hover over the member and click on the trash bin icon.
You could reassign the tasks to another member when you remove someone from a project.