[{"_id":{"$oid":"6516706a81f4dcd6d4e188c1"},"bom_data":{"loginTime":"123","description":"asdf","submit":"1"},"business_key":"Check_In_Process_e13ijeb9","created_at":{},"taskid":null,"updated_at":{"$date":"2023-09-29T06:36:26.642Z"}}]

db.collection.aggregate([{$project:{_id:1,loginTime:"'$bom_data.loginTime'",description:"'$bom_data.description'",business_key:1,taskid:1,updated_at:1,m:{$month:"$updated_at"}}},{$sort:{updated_at:1}}])