HELP ME PLS How to use craftbukkit

Hello, Im trying to make a server but i cant use craftbukkit, only spigot.I go on software, put 1.8 but i cant choose between craftbukkit or spigot. How can I use craftbukkit?I from Brazil, Im sorry if i wrote wrong.

I need help because there are some plugins thats only for craftbukkit, i use spigot so, these plugins dont work

Oh, ok, thanks for helping me!