You can't. Fuji's FP100C/FP100B is a pack film for the polaroid 100 series cameras, not the 600/sx-70 cameras. The pack films are too big.
Likewise the Fuji Instax is somewhat the right shape/size but the pod is on the side - on the long side of the picture not the short side, so you'd not have correct spreading even if you did load instax films into a 600 series pack.