Add "billing_phone" to register page and set password = billing_phone

Hi, first sorry for my english (I’m using a translator).

i want add custom field to register page ( my account woocommerce)

a) user register with email and phone number
b) password automatically generate with phone number and send to user with email
c) i want use function wp_password_generate() in pluggable.php to get phone number and set password = billing_phone