Information Gathering - Web Edition vHosts help

I’m doing a module called “Information gathering - web edition” and I’m confused on what input to give etc/hosts. In this example I’m able to spawn a target IP and given
“vHosts needed for these questions:
app.inlanefreight.local
dev.inlanefreight.local”
When im adding these domains to hosts should do I need to do this?
target-ip app.inlanefreight.local
target-ip dev.inlanefreight.local
And then change the IP manually every time a new target IP spawns? I just get confused on how i am supposed to enumerate other subdomains if I dont know what they are if I cant connect to them. Thanks for any help in advance! : )