Cisco makes a program call Packet Tracer that is a great virtual setup to practice commands and build virtual network setups. Not like the real thing as some bigger protocols and stuff arent fully supported but its another good start if you don’t have a lot of room for the full setup.
^^ isn’t that the one that requires IOS images to load on each device? I used one a while back and it was a full blown simulator but required your own IOS images.