Welcome Christoph.
You mention lith printing. It is something that I am currently experimenting with, currently mixing up various lith developer formulas that I have found, with my store of various chemicals. It is both exciting but also tedious at times, as the processing times can be very long at times, with nothing to see.
I too am reading, and maybe purchasing from a German site, which is full of information about lith:
https://www.moersch-photochemie.de/
And yes, I'm sure that you will learn LOTS from this site, as we all do.
Terry S