Welcome! I think its great you want to try and engage yourself in this amazing sim but in the end, it's safe to say you will most likely start kicking puppies after a few days of using just the keyboard. I cant even imagine trying it with a hotas an no trac ir at this point.
I hope you dont get too turned off by most responses on this. My advice would be, buy the game, start reading the manual, and use your keyboard to start learning everything within the hawg until you have saved up for a hotas/tracIR. That way when you do have it, you will have a bigger understanding of what does what and where what is.