The sound proofing won’t really work as it depend on the frequency. I had rock wool inside my plaster ceiling and still the sound will go through

Any suggestion ?

I am sure it works well as this is for car purpose. Suggestion how to install ?

remove all the plaster gypsum boards and frames of ceiling
attach/stick firmly and cover all the ceiling with a layer of 2mm or 3mm MLV sheets directly to the ceiling
then build ceiling stud, fill the stud space with rockwool 50mm 60kg/m3 mineral wool at least
then use 9mm at least gypsum boards to cover ceiling stud
then a layer of MLV again attached to the gypsum board again (ensure it is firmly attached and wont drop)

then build ceiling stud again, but this layer leave it with a gap of 6 inches at least with above, fill the stud space with rockwool 50mm 60kg/m3 mineral wool at least again

then use gypsum board to seal the ceiling as per what you have of your ceiling now