Squirreltown is right, there are a lot of variable pieces when it comes to building Roku channels, so we'll be better able to help you if you ask a specific question.
There are "getting started" resources available on our website that would likely be a good starting point for you: https://developer.roku.com/index
You also might want to check out the "How Roku Channels Work" and other guides on our blog: https://blog.roku.com/developer/getting-started/
Finally, we recently launched a new web tool that allows content creators and publishers to build Roku channels from a JSON or MRSS feed. This is the fastest and easiest (no coding required) way to build a Roku channel. It sounds like this will be the right approach for you. More info here; https://developer.roku.com/publish