Hi! Newbee po! Forged Birth certificate and denied paternal support since birth

Hi, I'm a new member, I'd like to ask for an advice, I'm 26 years old and is now a professional. I just recently knew about my fake identity. I've been carrying my step-father's surname since I was in Kindergarten, and my birth certificate was late-registered in 1992. I was born in 1985. My true birth certificate in which I bear the last name of my biological father was registered with the NSO and also the fake one that i'm now using. It was my mother's and step father's idea to forge me a birth certificate since I need it for compliance in school requirements in 1992. So, I was late registered by a local midwife they knew then. until now, I'm still using my step dad's last name. I was baptized in roman catholic using my biological father's name. Please help me on what are my rights in claiming from my biological father and how can I ask for them. I already know my biological father. he is now in California USA and we got to chat and email recently. What are the possible actions I may take against my real father now that he is in abroad? He was not able to provide me support since birth, so I was forced to work during my high school and college just to provide for my studies. Please help. and now, he's telling that he doesn't have any responsibility over me because I'm already in my majority age and that I'm already married. That I can no longer claim anything from him now.