what powers acctualy have members of secret society Rosenkreutz?

Answer 1

You mean the Rosicrucians.

There's fairly good, if not entirely unbiased, history of the group here: http://www.newadvent.org/cathen/13193b.htm

btw, the AMORC is not the same as the Roscicrucians. They are a modern society claiming an ancient and noble pedigree--a process called reconstructionism

Answer 2

esoteric knowledge. By-the-way, anyone can learn this knowledge by joining the Rosicrucian Order, AMORC.