Allow a user group read, write, execute access to a particular directory

I want to grant a group **"usera"** rwx permission to a directory. The directory is already owned by a user that belongs to this group **"usera".** The name of the username and group is same. **Current Permissions:** If I check the current permissions of that directory by running the following command: ls -la Following is the output: drwxrwsrwx 2 usera usera 4096 Jan 9 09:30 . Desired Output: drwxrwxrwx 2 usera usera 4096 Jan 9 09:30 . **Problem Statement:** The problem is that the above-mentioned **usera** doesn't have ssh access to the server. So, I have to login via another user with admin privileges. And I want to grant group **"usera"** rwx permissions on a particular directory /opt/test/abcd. But I am unable to figure out which command to run. I know we can grant permissions by using chmod command but how to apply it in this context