Integrated architecture

Operating system:Linux
OS version:Debian Buster
I have question about global architecture of webmin, virtualmin and cloudmin. In my opinion, webmin is server management iface, virtualmin is virtualhost management iface and cloudmin is VPS management iface . But how these are integrated. Where is the user management and user integration with virtualmin and cloudmin? I’am looking for a solution for the migration from imscp, on which we have about 40 customers, and for VPS management, which I currently do manually for 11 customers. I can’t find out where I manage customers and where I assign them either web hosting or VPS hosting depending on what they have set up. I’m looking for where to start a user and then where to assign web hosting or VPS hosting for his. Or are users based individually according to who wants what? If he wants web hosting, he must be created in virtualmin, and if he wants a VPS, then he must be created in cloudmin?