It's legal to hunt an elephant in some places but in other places it can still be illegal to hunt elephants especially if you hunt and kill the elephant and leave the elephants husks behind.
Some place such as Botswana is now legal to hunt elephants however if you do hunt elephants in Botswana you cannot bring any part of the elephant home.
So you would need to live in Botswana to hunt the elephant and keep the elephant.
If you live in the USA you cannot bring any part of the elephant from Botswana into the USA.
You have to check with your local laws in where you are if you plan to hunt an elephant because laws in different states and countries vary on whether or not it's legal to hunt and kill elephants.
Some places may impose a huge fine or even prison time when you're caught hunting or killing elephants.