When Fighting A Carno, a strategy you can use is:

-Gear up on spears, bows, arrows, and any kind of melee weapon. Then try and squeeze your player in between some rocks where the Carno can’t get you. Then just start to attack the Carno from where you are there. And if the rocks don’t work, try finding the nearest structure with an open door so you can get in and the Carno can’t and then start attacking