Oh, yes "Kha" ค่ะ is for females, and "Krub" ครับ is for males. I think it's similar to something like yes sir in English, but it is used more often, but it's not just mean "yes" actually you can put them in almost any sentences and phrases to make it more formal and respectful, like when you say "Thank You" you can put Kha or Krub after as "Thank You Kha(Krob Kun Kha)", in Thai we used Kra and Krub to Older people, Senior, Stranger, Parents, etc. pretty much anybody except your friends and we got so many pronouns which sometimes can be a pain in the ass to choose from lol
Nang and Khun are also used as an honorific in Thai, but a bit different, Nang = Mrs. (Married woman), Nangsao = Miss. (Unmarried woman), Nai=Mr., but Khun has used regardless their gender when you called someone with Khun before their name will make it much more formal and respectful.