It’s not going away. It’s still being maintained and written. And by golly, I’d like to learn it and use it!
This is an old post I know, if anyone wants to learn Cobol for the As/400, iseries, system i or whatever new name IBM wants call their boxes. I would suggest getting “Programming in Cobol/400” by Cooper, Stern and Stern.
It is an older book, but will teach the basics needed to write Cobol, including CRUD application. I wish I could find one that would walk you through developing a crud app in Java.