Will a fuse work successfully if it is connected in parallel with the device it's supposed to protect?

No, a fuse will not work successfully if it is connected in parallel with the device it is supposed to protect. Fuses are designed to be connected in series with the device, allowing them to interrupt the current flow when an overcurrent condition occurs. If connected in parallel, the fuse would not experience the same current as the device, and it would not protect it effectively from overcurrent situations.