Migrate foreman/katello content from one instance to another

Problem:
We have installed a fresh install of foreman/katello 1.19/3.8 in a new server and we would like to migrate all our clients, content views, repositories, etc from the old instance (foreman 1.16.1). I have been reading the forum and the foreman/katello documentation but couldnt find the steps. I read about Katello disconnect but I wonder if that would cover all.

Expected outcome:
Have all the current config in the new instance based on foreman 1.19

Foreman and Proxy versions:
Old instance: 1.16.1
New instance: 1.19

will the clients be re-registering to the new server?

Yes Chris, we will re-register them.