Hi,
My site has two content sections - content/blog/java and content/blog/go. I have different set of tags for java and go. I would like three different pages:
How do I achieve this?
Regards,
Radha.
There are lots of ways to organize your content and get that result. Please consult https://gohugo.io/content-management/ and try a few things. 
I sure did, before I posted the question here.
I’ve tried having _index.md in the leaf folders (go, java), and tried having _index.md in blog. But the posts don’t get listed like I wanted.
Any specific approach you could suggest?
More specifically, how do I achieve the tags per section part? Tags seem to be global, across sections. Is there a way I can specify a hierarchy?
I think you can do what you want using taxonomies all posts would live under the same blog section but the tags is what will decide where they render.
So make a blog taxonomy and then tag your posts with java or go.
Not that I know of. The taxonomies are flat.
I wouldn’t make a suggestion without seeing the actual content and current IA. You asked about creating three specific URLs, but I would never use that scheme, so I have no suggestions. 
I believe Hugo added a feature for this in recent update to archetypes, where you can specify different archetypes (which includes setting tags, etc) for different hierarchies.
I haven’t tried it, so I could be wrong. But you should try it out, and report back on how that worked
Could you point that out? I’m curious as to how that works.
As I said, I haven’t need to use this feature, as I use the structural hierarchy feature in Org mode. I simply tag an Org mode subtree with “foo” tag, and all posts under that subtree will have that tag.