Default whatsapp pl. help

first allow me to thank u all
i have levee my country
and i stopped my sim card and suddenly i have lose every thing in my phone

i get back my app bout i could not get the verification code for whatsapp in the number that my family and friend know

could any one help me
i have read that there is a way by activet it in a new number after move to system file withe some file whatsapp registered phone number and change it to any i want
can any one help me with