Create new Puppet class from scratch using Katello

I need to deploy some files to new created VMs. I think that Puppet classes can serve my purpose.
How can I create a new class from scratch? I don’t see the option.
Foreman and Proxy versions:
Katello 4.1.4
Foreman 2.5.4

Hey @marco.l
We have a guide here you might take a look at:

hey, thanks.
So am I understanding right if I say that I have to create a custom puppet module outside Katello and then I can push that module using Katello?

Second question: how can I get my hosts to report data like n. of errata needed to Katello? Do I need to install a Puppet agent on the host machines?