Shipping is a complicated matter. I know it's been discussed many times on this forum.
Here is one of the posts https://icraftgifts.com/forum/296/creators-please-consider-international-shipping/
I think the best way to get some of the answers to your questions is to talk to the shipping companies directly.
So if you normally use Fedex and plan to ship to a specific country, check with them if they have any specific requirements.