you should use the whereHas method to filter assessments based on the related user's status
here the reference
$data = Assesment::with(['age:id,age','curriculumUnit:id,unit_name','subject:id,subject_name','assesmentQuestions','user' => function($q) {
$q->select('id')->where('status', 0);
}])
->whereHas('user', function($q) {
$q->where('status', 0);
})
->select(['id','assesment_name','subject_id','curriculum_id','focus_area','age_id','description','created_at','status','created_by'])
->where('status', 0)
->orderBy('id','DESC')
->paginate($this->pagination_assesments_records);