Click R1 in the topology. The prompt ends in #. That single character tells you which mode you are in, and mode decides which commands the router will accept.
R1> is user mode. You can look, but only at a little.R1# is privileged mode. Every show command works here, and this is the door to configuration.
You land at # because the account you are logged in with, pinglabz, has privilege 15. Drop down a level with disable, then climb back with enable. The router asks for the enable secret, which is PingLabz!23. Nothing echoes while you type a password. That is normal.
R1#disable
R1>enable
Password:
R1#
Run show privilege to confirm your current privilege level.
R1#show privilege
Current privilege level is 15