GNU/Linux Debian Bookworm Installing Rtl8761B Bluetooth Driver Guide
How to Install Realtek Rtl8761B (RTL8761BUV/RTL8761BTV) Bluetooth 5.0 Driver on Debian Bookworm 12.x GNU/Linux – Step by step Tutorial.
And Rtl8761B Bluetooth Driver on Debian Bookworm should be present on Kernel, what may be missing is only the Firmware.

1. Downloading Rtl8761B Bluetooth Firmware
Download Rtl8761B Bluetooth Firmware on Debian GNU/Linux
Grab both: “rtl8761b_config” & “rtl8761b_fw” Files.
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