From least to maximum access, the permission levels for a repository are:

• Read: Recommended for non-development contributors who want to view or discuss your project.
• Write: Recommended for contributors who actively make changes to your Salesforce environments and projects.
• Manage Project: Recommended for project managers who need to manage the repository without access to sensitive or destructive actions.
• Deploy: Recommended for Salesforce Administrators or Salesforce Developers who are allowed to deploy releases to your Production environment.
• Admin: Recommended for team members who need full access to the project, including sensitive and destructive actions like managing security or deleting a repository.