Maybe you need help with the way we pronounce both verbs. On "casar" the "s" sounds like "z"... Like the s in "house" :)

On "caçar" the "ç" sounds like the s in "sound". 

Couldn't think of better examples, sorry :). Hope it helps.
Some other people already wrote about the completely different meaning of these two verbs - casar is to marry and caçar is to hunt. 

Portuguese language is about sound... This words can look the same but when you listen it's totally different after some time you will get this

Casar é se juntar oficialmente á um/uma homem/mulher podendo construir um lar.
Caçar é ir atrás de algo/alguém/animal que você precisa nalgum lugar. Pode ser por bem ou por mal. Ex.: Caça de animais para alimentação...
Não sei se pude ajudar!

Casar means marry with someone. Like, Tom Will marry with Eva = Tom vai se casar com Eva.
Caçar means Hunt. Like, I'll go Hunt a Bear tomorrow = eu vou caçar um urso amanhã
Got It?
My english is too good, but i'm trying :)

Casar means marry with someone. Like, Tom Will marry with Eva = Tom vai se casar com Eva.
Caçar means Hunt. Like, I'll go Hunt a Bear tomorrow = eu vou caçar um urso amanhã
Got It?
My english is too good, but i'm trying :)