How to reinstall android kitkat in HP Slate 7 voice tab using Mac

My HP slate 7 voice tab is stuck with its logo when I try to switch it on. I also tried to hard reset it by holding all the three buttons (volume up + volume down + power) but it gets stuck on "product mode" with no further changes on the screen. As I a noobie in this, any guidance is very much appreciated. PS: As its an old tab, I am also fine with rooting it just to have it up and running for a few more years, rather than throwing it away. Kindly help