Hello! Can I create my fork of Devuan Beowulf and Devuan Beofulf repositories?

What's devuan beofulf? Is it a new derivative unknown for me? Either way, the answer is yes, you can create a fork of these repositories in the same way than devuan forks the repository of debian. Indeed, that's what amprolla is for. Take as an example gnuinos, whose repository is a fully amprolla setup taking devuan as a base.

Yes, you can configure the sections in lib/config.py