YOU SAID:

my dad is coming up the stairs going to say hi

INTO JAPANESE

私の父は挨拶に行く階段を上ってくる

BACK INTO ENGLISH

Coming up the stairs to go to my father

INTO JAPANESE

私の父に行き階段を上ってくる

BACK INTO ENGLISH

Come up the stairs to my father

INTO JAPANESE

私の父は、階段を

BACK INTO ENGLISH

My father is on the stairs

INTO JAPANESE

私の父は、階段では

BACK INTO ENGLISH

My father is on the stairs