Only the project Admins have the permission to add or remove members to a project or change the member’s permission.
Learn more about project permission control.
Add project members
Click on the dropdown menu icon beside your project name, and select Edit members.
Next, click + Invite new member to invite people by entering their email addresses or their username.
You can also invite a new member by clicking on the assignee icon in the main panel and entering their email addresses or their username.
The newly invited members will automatically join the project once they accept the email invitations.
Note: When inviting a member to a new project or organization, the member will show up in the autocomplete dropdown menu if he/she has already been in the same project or organization with you before.
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.