Hi Muhammad,
Unfortunately, Pakistan isn't currently a supported region for the underlying payment system used by the Chrome Web Store. There is no specific reason I'm aware of why we can't accept payments from Pakistan, however, and we are working on trying to expand the regions where developer registration is available.
A workaround I've seen in cases like this is using a foreign address if you have one, or having someone else sign up on your behalf. I can't recommend either of those but it is something which has worked in the past.