Using of numbers in these examples

how do you know which number to use

i have one sister >jedńa

i have one brother>jednego

i have one dog

i have one cat

i have one son

i have one daughter

i have one book

etc, etc , ect

It depends on if the word is masculine, feminine or neuter.

For instance a book ("Książka") is feminine so we use "jedną",

for masculine we use "jednego" and for neuter- "jedno"

or 'jeden'

like: jeden dlugopis

look at the last letter of polish word in infinitiv-
if there is an -a you write "JEDNA" becuse it's female
and JEDNEGO in male

i have one dog - mam JEDNEGO psa (infinitiv - pies - male)
i have one cat - mam JEDNEGO kota (invinitiv kot - male)
i have one son - mam JEDNEGO syna (invinitiv syn -male)

i have one daughter- mam JEDNA corke (invinitiv corka - female)
i have one book - mam JEDNA ksiazke (invinitiv ksiazka - female)

ok thanks folks

Or jednego pana.