child regisration as british

my husband and i have just been granted british citizenship through eea route.
now we want to register our 2 children who are born outside the uk in france. my son is 9 year old and my daugher 5years old .
do i have to wait my daughter to turn 6 years old ( she does not old permanent residency) before applying for registration or can i apply anytime from now.
i am quite lost under which section do i have to registered them. is it under home office discretion even tough we are naturalisided as british?

my 3 child is born in uk and we were holding permanent residency at the time of her birth. is she british and can we apply for a passport straithaway.

thank you so much for your answer moderator