Uk citizenship problem

Hi Everyone
I have some questions
I hope you will help me
So i apply for my british citizenship and i have a problem of referees
my father is british but i was born in congo so i don't know british people and in the form they ask me to give 2 referees the first can be of any nationality but the second must be british but i don't know british people so my questions is can i give two referees of any nationality ?
And other question i make the application online and i answer all the questions after that i have to pay but i dont see where i can send my biometric document.. is it after the payment ?
Thanks

Can you elaborate on what path are you taking to citizenship?

Do you or have you lived in the UK?

If your father is British, did he become a British citizen before or after your birth? Was he married to your mother at the time of birth?