Can anyone help me with a japanese translation?

Tweet

I started learning japanese recently, so I'm not very advanced, I'd just like to know the translation of some words, I'm not sure of the correct spelling. I'd like to know how to write "friendship" and "never give up" using katakana or whatever other symbols appropriate. The translations I found were - kouyuu (??) for friendship and kesshite teagere (??? ??) for never give up. As I said, I'm just a beginner so I'm not sure if these are the best words to describe the meaning of the words I'm interested in, and neither if the order in which I put them is correct. Please tell me if I used the right words and symbols!