It seems clear from geologic evidence gather over the previous 200 or so years that life on this planet has passed through many different phases and forms. There have definitely been animals and plants different from present day creatures living on the earth in the distant past. There must have been some reason(s) for the succession of these different creatures. To be sure because of physical and physiological reasons the later more sophisticated creatures could not live until the environment was properly prepared for them. Only creatures that could exists at low oxygen levels could survive before an atmosphere with sufficient oxygen had been established. Oxygen producing photosynthetic bacteria and plants had to come into existence, multiple and thrive long enough to produce enough molecular oxygen in the air and waters for multi-cellular animals to live. There had to be sufficient food available before large marine animals could be introduced. Plants had to grow abundantly on land before animals could live on the dry lands. And fertile soil had to be produced before plants could grow. This world is such an intricate and complex environment and what it is today is the result of all that happened in the past.
We know quite a bit, about what is needed for an organism to develop and function. We know pretty much about the nutrients and physical conditions required for life and growth. The molecular structure and function of most organisms is largely understood and we can see that each creature consists of many systems. Each system is made up of many smaller systems and all these need to function together for the organism to develop, grow, and multiply. In short, each organism appears to be irreducibly complex. And the prospect of building even the simplest bacteria requires much more than just generating the DNA genome for the bacteria and then placing it in a nutrient-rich environment.