1 – First thing that you can try:

Create a .conf file and write in.
Like, /etc/modprobe.d/raspi-blacklist.conf and we should add the configuration below.

#Wi-Fi
blacklist brcmfmac
blacklist brcmutil
#Bluetooth
blacklist btbcm
blacklist hci_uart

2 – Second thing that you can try:
You can edit /boot/config.txt and add this two lines:

dtoverlay=pi3-disable-wifi
dtoverlay=pi3-disable-bt