Your question is interesting, but no single species has evolved through these steps. The ancestors of birds, which fly, walked on land without flying. The ancestors of those walking reptiles were fish, which swam. However, the ancestors of the animals we have today are now extinct (meaning that they are all dead).
By the time a group of animals changes a lot, it is a new species. What changes would an animal have to have before it could move from water to land? What kind of changes would a walking reptile need to have before it could fly?
Thanks for asking
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