RHOSTS not validating - it's not a missing -S

So..I'm running a Kali Virtual Box for a class. currently making sure everything is fully updated. When I run RHOSTS in Metasploit as part of a hack-yourself-first.com demo, I continually receive an error message that reads:

[ - ] Auxiliary failed: Msf::OptionValidateError The following options failed to validate: RHOSTS.

And I am 100% using the -S.

Any takers? I'll post my whole commandline journey to get to this point if you want. I'm just trying to RHOSTS > hack-yourself-first via scanner/http/https_hsts. or add a screenshot. whatever will help you see what I'm saying!

I really need help. Kali is not my first language.

Thank you all so much :)

+jmj+amdg+ttm+

before you start metasploit for the first time using msfconsole, you need to actually creat the database it needs..

msfdb init

msfconsole