Starting with the “how” to create publicly sharable content: there is an optional component of the Storj network called Link Sharing. To use Link Sharing, you first register your credentials with the Auth Service.
If all of your content is public, it’s often easiest to share an entire bucket with-in the storj.io user interface. You can also use the uplink CLI to make content available with Link Sharing. If you have a bunch of files that are semi-public, you can prohibit listing when you do this, so that people can’t browse for content.
For more details, please search the forum, there are plenty of details out there.