Hi again Zaina,
As for "kairo"....I'm sorry but I'm not sure what you are referring to. What is the context?
In Japanese, you conjugate verbs, that is, change the form of the verbs to make it mean different things. So "I can't come" and "I don't want to come" will be said by changing the form of the verb "come".
Besides, the Japanese translation for the word "go" is used in many situations that you would use the word "come" in English.
It is not advisable to translate "a word" taken out of context, simply because there are so many variations and different words you use in different situations. We don't want to give you the wrong advise. It would help if you can tell us the exact situation. Thank you.