@Gunesh P , you have to create a user in OS, login to Sandbox terminal as root and type
useradd abc
passwd abc
This user will not have sudo access, in order to give it, type visudo and add this line under root:
## Allow root to run any commands anywhere
root ALL=(ALL) ALL
abc ALL=(ALL) ALL
Save the file and after this, you can do SSH and later on, you can give this user read/write access through HDFS policies of Ranger.