Database
[{"confirmed":[{"confirmed":100}],"denied":[{"denied":50}],"pending":[{"pending":20}]}]
Query
db.collection.aggregate([{$project:{res:[{category:"confirmed",count:{$first:"$confirmed.confirmed"}},{category:"denied",count:{$first:"$denied.denied"}},{category:"pending",count:{$first:"$pending.pending"}}]}},{$unwind:"$res"},{$replaceRoot:{newRoot:"$res"}}])