Need help about salary

Hello poo. Basically newbie, tapos I was offered the role and then kagabi nag-onboarding kami and this morning sinend sa akin yung contract (parang baliktad nga yung process HAHAHA). So ayon, during the call kasi I was told about the salary I'm getting tapos yung nandon sa contract ay lower by 30-40%. Idk if I can negotiate that although I do have some experience sa field pero wala akong salary non, parang hobby to naging work ganon. The contract also states na I would only get my pay after the final approval.. so there’s risk na baka istall nila yung approval and my pay.