I play other full screen games while my account bots, so I don't see why you can't too I think if anything, the limiting factor will be whether your computer can handle a bot + another high intensity program like BF.
Kaze is right, it depends entirely upon your processor and RAM. If you have less than 8gb RAM or a processor that isn't an i5 or better then you wont be able to without massive lag. Put Runescape on the lowest settings possible if you do try to do this.
