and can i bring the box already taped up, or do i have to still show them what im sending?
im sending it to another country.
yes and yes
yes you can use a fedex box and send out of the country
(the post office doesnt care what type of box as long it has postage on it)
but you will still need to fill out some customs forms and whats insdie
the box and value of that item
you should cover any markings on the box if it has already been used for shipping though