Does Multiverse answer the Fine Tuning Argument?
It possibly could, if it is shown that physical constants actually exist over all possible ranges. If so, then it would explain why we have the appearance of fine tuning.
Does Multiverse answer the question "Where do the laws of physics come from?"?
No. Because in the setting of the Multiverse, there would still be a set of more fundamental bedrock laws whose origin will not be accounted for.
Martin Rees: One Universe Among Many?
"An astonishing concept has entered mainstream cosmological thought: physical reality could be hugely more extensive than the patch of space and time traditionally called “the universe.” We’ve learnt that we live in a solar system that is just one planetary system among billions, in one galaxy among billions. But there are signs that a further Copernican demotion confronts us. The entire panorama that astronomers can observe could be a tiny part of the aftermath of our Big Bang, which is itself just one bang among a potentially infinite ensemble. In this grander perspective, what we’ve traditionally called the laws of nature may be no more than parochial bylaws—local manifestations of “bedrock” laws that must be sought at a still deeper level."
Gary Gutting: Can Physics and Philosophy Get Along?
"But, the philosopher says, What about the laws of physics? They are something, not nothing—and where do they come from? Well, says Krauss — trying to be patient — there’s another promising theoretical approach that plausibly posits a “multiverse”: a possibly infinite collection of self-contained, non-interacting universes, each with is own laws of nature. In fact, it might well be that the multiverse contains universes with every possible set of laws. We have the laws we do simply because of the particular universe we’re in. But, of course, the philosopher can respond that the multiverse itself is governed by higher-level laws."