You didnt mention your Roku stick model # and firmware version: Settings/System/About
For official remotes, either the $20 Voice Remote (RCAL7R) or $30 Voice Remote Pro (RCS01R) can be used, and can be obtained from Roku.com/Walmart/Best Buy/Amazon/etc.
https://www.roku.com/products/accessories/streaming-stick
As for the Roku TV, what is the WiFi issue?