'nega(네가)' is you. n 'naega(내가)' is i.
i think maybe u talk 'naega'
I speak to Korean '나(na),내(nae),저(jeo),제(je)'
You speak to Korean '너(neo),네(ne),당신(dangsin)'
people scarcely say "네가(you)" to other one, but use much when writing.
"저","제" r low(humble) talk.
"당신" is honorific talk.
it is used in this situation when people say to 1st meet or unfamiliar or older man etc.