Difference between 那 vs 呢 and when to use it
哪:
1.
Question words. Ex:  Where is he?  他在哪兒？ , How do I know?、我哪兒知道？
2.
After the end of nasal rhyme. Same to 啊 . Ex: 天哪！  (天啊!)
3.
哪吒:A fairy in a Buddhist story. In the novel, there is a story that the broken bones return to the parents and appear as the parents. Or called 哪吒三太子.
呢:
1.Whispering. Metaphor the euphemistic voice. Ex: 細語呢喃
2.Auxiliary word.

2.1 Show the problem. Ex: What should I do? 我該怎麼辦呢?
2.2 Show confirm. Ex: It's still early! 時間還早得很呢！
2.3 The tone of the expression stops. Ex: Although your travel plan is very attractive, but! I don't want to go at all. 雖然你的計畫很吸引人，可是呢！我一點都不想去。

那:
1.Demonstrative pronouns. Ex: 那天、那本書
2.Tone words that express acceptance and transition. Ex: If you have something to do, then I will find someone to go. 如果你有事要忙，那我就找別人去