|Generally speaking, when running cabling in the walls of a building they should all terminate at the same place. Typically to a "patch panel".|
You need to figure out where the network cables in your condo all terminate in order to setup a connection from your bedroom to your living room.
Once you know where they terminate, then you have to figure out which is which (bedroom/TV room) and connect a patch cable from the one to the other. At the bedroom end of this, you would plug into your SOHO Router and of course at the other end, your Roku device.
What you're missing right now is that "jumper" connection to join the TV room to your bedroom.