Your first question is discussed in the book The Recursive Universe by William Poundstone (1984).

One of the chapters asks "what is life?". It considers (and rejects) various options, and finally settles upon a definition based on Von Neumann-style self-replicating machines using blueprints and universal constructors, and explains why this is the most (only?) meaningful definition of life.

Later, it talks about how one would go about creating such a machine in Conway's Game of Life. When the book was written in 1984, no one had actually created one (they need to be very large, and computers weren't really powerful enough then). But in 2010 Andrew J. Wade created Gemini, the first successful self-replicating machine in GoL, which I believe meets the criteria - and hence is "alive" according to that definition (but only in the sense that, say, a simple bacteria is alive). And I think it works somewhat like how it was sketched out in the book.

Another chapter estimated how big (and how densely populated) a randomly-initialized hypothetical GoL universe would need to be in order for "life" (as defined earlier) to appear by chance. I don't recall the details - but the answer was mind-boggling big, and also very sparsely populated.

All that only gives you life though, not intelligence. But life (by this definition) has the potential to evolve through a process of natural selection to achieve higher levels of complexity and eventually intelligence, at least in theory.