You don't observe it. Frankly, scientists do not have the answer either as to how life started.
But that’s what evidence are - observations.
Observations of the natural phenomena or physical phenomena.
Observations are also whatever “data” or “information” that you can obtain from the evidence, such as quantities and measurements, or just detections.
Evidence and data are what can refute or verify a model (eg scientific theory, hypothesis, theoretical model, etc, are models that explain and predict the phenomena).
No model or concept are ever true “by default”.
Every model or concept must be TESTED, before you can determine if it true or false, verified or refuted, science or not science.
And the only you can test a model, is through observations, and that means evidence or experiments or both, and data.
Creationism and Intelligent Design cannot be tested, because God or the Designer cannot be observed, measured or tested.
And there are no observations of God and no evidence of God.
“No evidence” means the “absence of evidence” or “zero evidence”.
No evidence means Creationism or Intelligent Design are unfalsifiable and untested. And if it untestable, it means it cannot be tested.
Without observations and without evidence, concept cannot be “science”...it is that simple, but you stubbornly cannot understand it.
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