These are two completely different skill set of careers.
1. Depends on your interests.
2. Also depends on what you are good at
Nursing will have to do mostly about Biology. So you need to be good at that. And it will also be a career you will be taking care of people.
HND in Information technology on the other hand requires a bit of math and other aspects of science aside biology. so you should know where you are good at and what you will want to commit your life to.
Information technology is hitting grounds now in the modern world. And needs more people.
On the other hand, nurses get posted right after school. So no need to struggle to get job if you cant create one on your own.
So its all about your choice and interests.