Citizenship with minor child

My (American born) son and I are wanting to apply for citizenship soon. He is a minor so i have a few questions
1- I was wondering if I need proof of him residing in the country exactly 3 years and a day before the date of the application or if that only applies to me?
2- I’m confused if he can apply with me or not. It sounds like I’ll have to have my citizenship before he can then apply for his?
3- I have sole custody and in my court paperwork it states (which his bio father agreed to hence it being ordered) that when the time came that our son would be able to apply for citizenship. With this ordered in the court paperwork, will I still need a letter from his bio dad giving permission for him to obtain his citizenship?

My (American born) son and I are wanting to apply for citizenship soon. He is a minor so i have a few questions
1- I was wondering if I need proof of him residing in the country exactly 3 years and a day before the date of the application or if that only applies to me?
2- I’m confused if he can apply with me or not. It sounds like I’ll have to have my citizenship before he can then apply for his?
3- I have sole custody and in my court paperwork it states (which his bio father agreed to hence it being ordered) that when the time came that our son would be able to apply for citizenship. With this ordered in the court paperwork, will I still need a letter from his bio dad giving permission for him to obtain his citizenship?

I answered this on your previous thread.
https://talk.uk-yankee.com/index.php?topic=100734.msg1324148#msg1324148

Did you check on the links I gave?

I don't know if you went to immigrationboards.com and asked about your question 3? This has just been asked by somebody else on there.

https://www.immigrationboards.com/british-citizenship/eligibilty-criteria-for-children-with-ile-t339290.html

https://www.gov.uk/government/publications/children-nationality-policy-guidance/registration-as-british-citizen-children-accessible#bookmark88