What specific channels are you looking for? You could do a search in the Roku app store to see if they have what you are looking for.
such as CNBC. I'm new to Roku and didn't see any on the live station list.
CNBC has a Roku app in the store; however, you need some type of cable/satellite/provider subscription to watch that channel.
If you search for particular channels in the Roku app store, you can see if there is something you are looking to watch. Some apps will require some sort of subscription though.
If looking for a free financial channel, Bloomberg is available via PlutoTV, PlexTV, and as a standalone channel. https://channelstore.roku.com/search/bloomberg
All the above can be installed on your Roku device.
Here is the website versions of bloomberg. (install pluto, plex, or tlc to get the Roku app versions from the Streaming Store.)
https://pluto.tv/us/live-tv/54ff7ba69222cb1c2624c584
https://watch.plex.tv/live-tv/channel/bloomberg-tv-2