Willl you still be able to bend your finger if you fractured the knucke?

Possibly: Depends on how bad the fracture/break was, whether the joint surface is aligned properly. If so, once it heals up should be able to bend but there is a high chance of some loss of the range of motion ie some residual stiffness as a consequence and any break involving the joint surface can lead to post-traumatic arthritis (joint pain from the damage to the joint surface).