Post a post to linkedin groups

Hey! Question.
I have been thinking about this for a while but I cannot figure it out.
There is some documentation on this I think:

From:

But I simply cannot figure it out. So we have a personal linkedin and say we are in ~20 groups. We want to (based on some make.com filters, but don’t worry about that) post some automatic posts to some of those groups. Ideally with an image or a document attached. How can we do this? Is this even possible?
Thanks! Would be huge