I’m not quite sure what this is asking but if i had to guess , it would be because native americans traditionally used the sun as a way to tell time instead of the more commonly accepted way which is clocks
I think they needed to learn time because like us, they needed to know when they were going to a specific thing like for example their time to go fishing or something like that. They also needed to learn it because they didn't have a clock as we did. So, that is why it was important for the Native Americans to learn time.