searching for biological father

any advice or inquiry messages appreciated:

i'm searching for my biological father and i have very minimal information to go off of. not even sure if a private investigator could help but i also can't afford because I heard they average $20-30 and hour. Here's what I know: -His first name only. -His race/ethnicity. -I know a couple of the cities he lived in at one point. -I know that my mother filed a restraining order/protection order against him around the time I was born. (I contacted 3 different county courts offices and clerks of differently levels asking for records on the but they couldn't find anything and said likely because it's been so long, the case was purged. since as far as i know, she did not renew it or make it last permanently.) -I know him and my mother were not married -I know he was not on my birth certificate, but he was at the hospital the day I was born. -When my mom married a different man years later, he legally adopted me and so I believe that my biological father had to sign some sort of release of parenting when that happened. -I have one poor quality photo of my bio father and mom and already tried reverse image searching and didn't come up with anything.

I'm trying everything in my power not to ask my mother bc we don't have a good relationship and it will cause drama and she will freak out and likely not help me in the end anyway.

I desperately want to find him to get answers to my past medically, and know other family and know my culture more. With the current state of the world I'm also afraid there's a chance he could've been deported or detained and I'll never find him if he leaves the US. I'm 22 years old and have no never met him and never really wanted to until having the strong urge to in the past year and a half