creating intermediate ca signed by an external root

[heidricha]

I don't understand the concept of creating an intermediate ca.

In my understanding, it should create a full CA, but instead of the ca.crt, a csr should be created, and after getting it signed with the root-CA, the ca.crt should be uploaded. it works this way using easy-rsa f.e.

here, when I create a ca with "intermediate": true, and "parent_common_name" added, the resulted CA data will contain only keys, and "isIntermediate": false

It's my issue tbh, but how this flow supposed to work?