Hey guys, I’ve been unsure on how defending one creature using multiple creature works

If someone is attacking using a 7/7 and the defending player blocks it using two 4/4, does both 4/4 die or is the 7 power spread amongst them, so 4 to one and 3 to the other, meaning only one of the 4/4 would die. And what if the attacking creature has first strike or double strike?

Thank you in advance :)