While there is no direct official PDF download link for a specific "RK908 Bluetooth keyboard" manual, the
The physical switch on the back must be set to “Bluetooth” (not “OFF” or “Cable”). Also, check that your device allows Bluetooth input (iPadOS sometimes blocks external keyboards in certain apps). rk908 bluetooth keyboard manual link
One of the best features of the RK908 series is the built-in RGB backlighting. You can tweak the look without any extra software: While there is no direct official PDF download
[Insert link to manual]
Since you need the to understand the shortcuts, here is the complete cheat sheet: You can tweak the look without any extra
: The RK FAQ Page provides official troubleshooting and pairing guides for all RK models.
I can give you the exact menu path for those settings if you're stuck!