Por que no te despides de mi = Why don't you say goodbye to me
Translation: Why don't you give your own money?
If you mean the Spanish ''por'' as in the English ''for'', its για (gia).
por kay (spelt 'por que') is simply "why"; e.g. 'por que no?', "why not?"
"¿Por qué [k] no?" It means, "Why not?"
por auto = by car
es por ti = is for you
"why not?"
por la vida= for life
"¿Por qué corres?" means "Why do you run?"
"Loca por ti" means crazy for you.
Depending on context, it can mean several things. For, by, through. It is also used in many idiomatic expressions that are taken as a whole, por aqui, por favor, etc.
it means: for Or: by