How would I create an isolated network of VM's for testing purposes

[adamthompson43]

Apologies if this is a trivial question but I've tried to find the issue online and I just need some guidance

I have a network forensics class that requires me to use Kali to find vulnerabilities in Windows XP and Metasploitable and need to set them up so that they can communicate with eachother, while XP and Metasploitable cannot access the internet.

I've tried using the option to isolate the VM's from the host but had no luck.

Any help would be appreciated.