There are 7 theories regarding the origin of life-
1. Interaction of chemical compounds over a long period of time, under a protecting cover of ice.
2. The action of lighting to form increasingly complex organic molecules.
3. Panspermia-life arrived on space debris, as per Tardigrades space creature.
4. RNA- I'm not too sure about this one. IT presumably takes over after one of the first two.
5. Clay- presumably similar to1.
6. Submarine Hydrothermal Vents- Its also presumably takes over after one of the first two, perhaps in conjunction with 4.
7. Inevitability- Given the right set of conditions, i.e an external source of energy.