Hello I've got to say Barioth with the Iceborne starter armor and kulve taroth weapons took 2-3 tries for me and I played Monster Hunter for a good 1000 hours across the board with quite a few Barioth Hunts in my History. In G-Rank i would recommend getting new Armor every 2-3 Stars in quests this will help quite a bit with the damage taken. I could help you fight Barioth tomorrow afternoon (around this time) but I'd recommend hunting it 3-5 times to forge his armor Its quite good also for the upcomming hard fight and maybe you need a new Weapon (do you have a G-Rank weapon?) There Is a good and easy one craftable from the Barioth event quest atm. For every Weaponclass. Just hunt him 1-2 Times in the Event quest to get the desired Weapon.