To find the group name of a folder in Unix or Linux, you can use the stat command followed by the path to the folder. For example:
stat /path/to/folder
This will display information about the folder, including the group name. The group name is shown under the "Group" heading.
You can also use the ls command with the -l flag to display a long listing of the folder's contents, which includes information about the group owner of the folder. For example:
ls -l /path/to/folder
This will show the group name in the group owner field of the listing. The group owner field is the third field from the left, and it is typically shown in the format groupname:.
You can also use the id command to display information about the group membership of the current user. For example:
id
This will display a list of the groups that the current user belongs to, along with the user's user ID (UID) and group ID (GID).