What is the difference between chuig and first?

chuig | first |

As a preposition chuig

is to.

As a adjective first is

having no predecessor the ordinal number corresponding to one.

As a adverb first is

before anything else; firstly.

As a noun first is

(uncountable) the person or thing in the first position or first can be (obsolete) time; time granted; respite.