Database

db={"issue":[{"_id":ObjectId("612775fbd237d9769a9fc3e4"),"tittle":"Weekly Issue1","data":[{"categoryId":ObjectId("61272e7dd237d9769a9fc3d9"),"articles":[ObjectId("61272f29d237d9769a9fc3da")]}]}],"category":[{"_id":ObjectId("61272e7dd237d9769a9fc3d9"),"name":"News"}],"article":[{"_id":ObjectId("61272f29d237d9769a9fc3da"),"title":"Some News","url":"https://www.google.com"}]}

Query

db.issue.aggregate([{$unwind:"$data"},{$lookup:{from:"article",localField:"data.articles",foreignField:"_id",as:"data.articles"}},{$lookup:{from:"category",localField:"data.categoryId",foreignField:"_id",as:"data.categoryName"}},{$addFields:{"data.categoryName":{$arrayElemAt:["$data.categoryName.name",0]}}},{$group:{_id:"$_id",title:{$first:"$title"},data:{$push:"$data"}}}])

Result