Are evolutionists only concerned with how life on Earth has EVOLVED?
OR do evolutionists also suggest how life on Earth began?
Certainly
evolutionists are interested in how life on Earth began - it's hard to imagine anyone who wouldn't be interested in such a tantalizing subject - but the
theory of evolution isn't about the original origin of life.
Since the origin of life was surely chemical, studies in abiogenesis are the bailiwick of of biochemists. Here's a big long article about the subject:
Abiogenesis - Wikipedia
Chemistry is a little over my head, currently, but maybe you'll find that helpful. And surely some of our resident chemists could address whatever questions you have?
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