First, you need to create a ubt0.conf file in /etc/bluetooth. Login as root open a terminal and run these commands:

cd /etc/bluetooth
touch ubt0.conf
ee ubt0.conf

Then enter the following:

authentication_enable="YES"
connectable="YES"
discoverable="YES"
role_switch="YES"

Next, edit /etc/rc.conf and enter the following

sdpd_enable="YES"
hcsecd_enable="YES"

If you have a recent intel bluetooth device, such as an AX200 or similar, you need to install the needed firmware:

pkg install iwmbt-firmware

Also obexapp and openobex to send files

pkg install obexapp openobex

Then create a folder to receive your bluetooth files:

mkdir /var/spool/obex

Then reboot

shutdown -r now

When boot up is finished, pair GhostBSD with your Android phone. There's a utility to do this in GhostBSD called bluetooth-config. Turn your phone on and go to Settings then Connected Devices. Login as root in GhostBSD then run in a terminal:

bluetooth-config scan

In the terminal you'll see output like:

Scanning for new Bluetooth devices (Attempt 1 of 5) ... failed.
Scanning for new Bluetooth devices (Attempt 2 of 5) ... failed.
Scanning for new Bluetooth devices (Attempt 3 of 5) ... done.
Found 2 new bluetooth devices (now scanning for names):
[ 1] 48:88:4a:g8:f6:97 "xxxxx-xxx (ubt0)" ()
[ 2] 14:50:88:e8:44:86 "AQUOS sense7"
Select device to pair with [1-2, or 0 to rescan]:

My phone is the aquos. If your device is found enter the number. In my case I would enter 2. If your device isn't found , rescan by entering 0.

Then your phone will be added to bluetooth hosts, and you can give your phone a name. If you give your phone a name, it makes things easier because you don't need to keep entering your phone's bluetooth address.
Then put your phone in pairing mode and enter a pin nimber in the terminal. 4 digits should be ok.
Then press enter and on your phone will be a request to pair with your computer. Enter the pin number you made previously and then you're paired.

Now to test if bluetooth is working start the obex server. As root:

obexapp -s -C OPUSH
-s means start the server
-C is the channel you'll be using

Then make sure your phone is on and open another terminal and as normal user enter

obexapp -c -a yourphonename -C OPUSH

Now obexapp will scan for all phones with the name you gave it while using bluetooth-config
Sometomes the first time is not successful. Just try the same command again. If successful, you should see in the terminal

you@you-ghostbsd ~> obexapp -c -a yourphonename -C OPUSH
obex>

This means you are paired. Now send something like a picture from your phone. The sent file will go to /var/spool/obex
If you want to send a file to your phone put in the terminal after obex>
put /where/the/file/is/pic.jpg
eg put/home/yourname/Pictures/pic.jpeg
And you'll get a notification on your phone that a file is ready to be received.

After the file is sent, enter

In the terminal to disconnect your phone
That's it