Fish, amphibians, reptiles and birds are alike because
1.) Fish and amphibians can both swim
2.) birds and reptiles can both climb, and there are some lizards that can glide there way down. They are known The Draco sumatranus lizard.
How are they different?
1.) Birds and amphibians are both different because some birds can swim (Like ducks, swans, Loons, Dippers, etc.) Most birds are unable to swim.
2.) Fish and reptiles are different because because fish swim and reptiles don't.
Hope this helps :D