Different answers are no doubt possible depending on one's defintion of "life." For me, the first life was single cellular organism, that was able to produce more of it kind, very likely by dividing into two parts. They would obviously be smaller, so not yet quite "more of it kind." Thus another atribute of "first life" is the ability to taken non-living matter into it "body" (the single cell). That would require taking some energy from the enviroment to reduce the intra cellular entropy - i.e. organize the injected non-living matter into part of functioning cell as it grows. To distinguish "life" from a growing crystal which does some but not all of this, I would also add that first living cells had a well defined boundary or "skin" (a cell wall). There are many ways that the first living cell could have been formed by natural processes. For example molecules, some what like modern detergent form naturally. They have one end that is hydrofilic and one that is hydrophobic. They spontaneously mutually align and form great sheets of "skum." Ocean waves would occasionally roll this skum into tubes, and even "pinch off" the tube ends to make a volume with well defined interior separated from exterior world. Most of our cells have cell wall made of hydrophobic and hydrofilic ended molecules, I think even today. Most of what would be trapped inside the pinched off skum would just be H2O but there would be some with various amino-acid molecules etc. too. Among the zillions of these closed volumes present at any one time on the primative ocean surface, most would not qualify as life, but over a few million years one did. Then evolution was off on it great adventure to see what would result. BTW, Last time I seriously considered this question I decided that there were other ways, which used the organizational abilities of crystal surfaces to do the creation of first life more rapidly, but explaining them is more complex. The problem in NOT to find one method by which life is expected to naturally arrise, but how to chose between the many posiblities which one is more probable to have been the origin of life.