I have Raspberry pi 4

Disable onboard WiFi on Pi 3B, 3B+, 3A+, 4B and Zero W.

dtoverlay=disable-wifi

Disable onboard Bluetooth on Pi 3B, 3B+, 3A+, 4B and Zero W, restoring UART0/ttyAMA0 over GPIOs 14 & 15.

N.B. To disable the systemd service that initialises the modem so it doesn't use the UART, use 'sudo systemctl disable hciuart'.

dtoverlay=disable-bt

Firmware overlays README