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The word "evolution" is commonly used as being synonymous with "naturalism", the idea that nature is "all there is". The "Theory of Evolution" as described by Darwin refers to biological evolution - the formation of new species through gradual change. The larger questions of how the first life was formed or how the materials of the universe came into being are part of naturalism but scientists do talk about the "evolution of the universe". Theories of how the universe came into being belong to a field known as "cosmology", while "abiogenesis" refers to theories of how the first life came about. Each field is very speculative.
Scientists believe they can describe the formation of the universe back to a small fraction of a second from its beginning. They believe the "Big Bang" explosion (a rapid expansion of space) was "lumpy" (non-uniform) and gravity caused clumps of matter to condense into stars. The main proof of the Big Bang is the observation that the galaxies of the universe appear to be moving apart from each other (the Doppler shift). If the universe contains enough matter then the expansion would reverse itself (because of gravity) and the whole thing would (possibly) start again. Many people like this idea because it avoids there being "a beginning", but for now there is not enough known matter to cause this eventual contraction (which is why scientists speculate about the existence of so-called "dark matter" to provide the "missing" mass).