hello I would like to know what to do because when I want to make a flight from EDDF to NZCH the consumption of kerozene is not compatible the plane consumes a lot of fuel is there a solution even for an lfpg flight to kmia 

Use the simbrief template that calculates the weights and values for a 747-8, as that's what this 777 thinks it is.
I recall a post where CS "may" alter the weights somehow, but not sure how it works when your 2 engine visual model is sipping fuel from 4 engines in the background....unless that is going to be edited as well in the future.