You can share a project by clicking “Share” on the cover of the project, pressing “Copy links” and paste the link to your team members or colleagues.
Optionally when trying to share the project, you can select "Also invite your partner to become a project member." Once selected, the one that has received this share link gains access to join your team instantly.(Note that only the project creator and Admins get the permission to check or uncheck this option. )
Set Share Permissions
To set the share permissions of a project, click "More" on the cover of the project, choose "Settings" and check or uncheck the option saying "All team members can share this project". (Note that only Admins and Super Admins have access to this option.)