...dad is 100% polish - my mom is 50% polish 50% German what am I?
"german" and "polish" are not discrete biological categories... like most large ethnic labels there's a fair amount of admixture from other groups.
biological reductionists might come up with dumb answers like 75% Polish and 25% German, but that's not how genetics work.
more important questions:
where and how did you grow up?
what language(s) did you naturally acquire while growing up?
where feels like 'home'?
where feels like 'hmmm nice, but not home'....