''Ne kadar'' means ''how much'' for askin to price -It's a pattern sentence- ''Nasıl'' means ''how?'' in ''Nasılsın'' (how are you?), ''how was your day'' (Günün Nasıl idi/Nasıldı), ''How is the weather'' (Hava nasıl?)
*''Ne'' means ''what'' but it also using in sentence ''ne kadar''(how much), ''Ne zaman?'' (literally means:What time, When), ''Ne yedin?'' (what did you eat?)
Suppose you meet a famous person. I want to know what he what kind of person he is: I ask "What is he like?" (This is very natural English) I think this is " O nasil?" in Turkish. If you visit a sick relative in hospital I would ask "How is he?" This question is definitely about physical or mental health. At present I think: "O nasil gibi?" is more like "What does he resemble?" "O nasil?" could be about health, but could also be about someone's personality.