Dual national traveling to Pakistan

Hi senior members one of my friend is dual national holding British and Pakistani passport he don't have NICOP card but his Pakistan passport is valid. Can he travel with both passports without visa. Which passport details he need to give to book the ticket ?
Regards

it doest matter or any problem of dual nationality

also no problem if there is no nic(nadra id) as nadra id card number is mentioned on pakistani passport
if he could show his pakistani passport to immigration officer he wil be fine