AA2
From what I read about your capabilities, at this time, I really would suggest you try to re-home lil guy to someone that has a pigeon loft. I know your intentions are sincere, but in reality, I don't think pigeon will live a long life, if you provide him with a solitary cage outdoors on your porch. If you allow him to randomly leave that cage, he is likely to become hawk dinner in not too distant future. You did mention there are hawks nearby in park.
Pigeon would make an excellent indoor pet if he was to be kept as a solo. I will tag
@Serin and see if he may have better advice for you than what I provide.
WISHING YOU BEST,,,,,,,,,,,,

for saving him,,,,,,,,,,and