hi B0mbV0yage2.0
im not sure because i havnt tried it but i think this is what you are looking for
How to play BFBC2 with offline bots - Mod by Napisal (youtube.com)
You may also have a look at Napisals youtube for more info, these are from his work Napisal Mod Channel - YouTube but sadly he has not continued his work for a long time and many of the links in his videos are no longer available.
hope thats what you were looking for