What are the various levels of Heaven?
Here is a broad “roadmap” of the range of spiritual levels, from “above to below.” This involves some deeper spiritual topics which are discussed in Chassidic teachings.  It may seem like an abrupt introduction with several new terms and concepts. But if you study it carefully detail by detail, it should make sense as a logical process.
If there is kindness in this world, it is because there is Kindness from a G-dly attribute in Atzilus?
Yes. The Ten G-dly attributes are the “building blocks” for the entire spiritual and physical creation, as they can be combined in infinitely many different ways.
If the Garden of Eden is split between Beriah and Yetzirah, did it exist on Earth in Asiyah?
The original Garden of Eden was on Earth, because Adam and Chava were created as immortals and G-d was dwelling together here with them. If they had not sinned, the state of ultimate spiritual bliss would have always existed in the physical world, as G-d desired it to be. Their sin brought death into the world, by which the soul is separated from the body. Until the culmination of the future Messianic Era when the world is perfected (may it come speedily in our days!), the souls must suffice with receiving their reward in the spiritual worlds.