As we move to Automation, there will be less need for CLI, but it will still be essential to have knowledge of the command line. There are so many commands on Cisco Switches/Routers. Type 'help' or '?' at the prompt to see them all:
00:00 - Top 10 commands on Cisco Switch
00:25 - 1. show running-config
00:59 - 2. show interface summary
01:24 - 3. show interface status
01:48 - 4. copy running-config startup-config
02:10 - 5. show cdp neighbour
02:31 - 6. show ip route
02:52 - 7. show version
03:16 - 8. show mac-address
03:35 - 9. ping ip (ip-address)
03:59 - 10. configure terminal
This is just a simple introduction to the CLI. This is using GNS3, but there are many different ways to simulate a network. Virtualisation is the best, such as GNS3 or Eve-NG.