If a child’s mother is Jewish, the vast majority of Jewish communities will accept that child as Jewish. If a child’s father is Jewish but the mother is not, then Reform and Reconstructionist congregations, and other Jewish progressive communities (Renewal, Humanistic, etc.), will accept the child as Jewish if he or she is being raised Jewish.
I’m not Orthodox, or even close. So I posted your question in a Facebook group I’m a part of called God Save Us From Your Opinion: A Place For Serious Discussion of Judaism, which I know many Orthodox Jews are members of.