I know what's the problem now. i deal like 2 damage on attack, I'm low level and haven't progressed side quests thanks for the hint bro ill do what you said after i grind
If you want to grind some levels i would recommend, equipping the initiate's robe, it boost experience by 25% .
You can get it from encountoring yoshi twice in the last map of the first area called "Visit feline hunting grounds". You have the chance get the encounter by interacting with the red/orange flame orbs , you normally get rare monster girl encounters from.
You should level up to like Level 15-20 before this fight
Another way to become stronger is to collect the orbs that look like the globes/sphere's from the puzzles, because each red one increase your HP by 10 (until you hit 999)
Each blue one increase your mp by 1 there seems to be no limit how much you can increase your mp, the max mp you can can probably have is likely also 999mp, but i can't confirm since highest i got, was a little over base 200mp.
The best equipment for the fight , for you is most likely.
Mr fist/warm cloth/ Vertebra of eternia
The best skills are:
Overpower (Veteran's armor)
Regrowth (shaman's garb)
Meditation (Priest's robe)
By the way you should try get all skills these are the most important one's at least in my opinion.