How to correctly save references to mongodb from request

Question

I want to save data and references of child document into parent document from request, I have managed to achieve that, but I am not sure is this correct way of doing it. I have found in stackoverflow that first we have to save child document. so we can save references of child document into parent document

This is my structure of request

"category": "movie",
"overview": "This is overview",
"poster_path": "https://image.tmdb.org/t/p/w500/aWeKITRFbbwY8txG5uCj4rMCfSP.jpg",
"release_date": "2021-12-01",
"title": "Sing 2",
"vote_average": 8.2,
"cast": [
    {
        "name": "Matthew McConaughey",
        "profile_path": "wJiGedOCZhwMx9DezY8uwbNxmAY.jpg"
    },
    {
        "name": "Reese Witherspoon",
        "profile_path": "6Pp3BrY2JbJg77Po8NOBO6zOA8m.jpg"
    }
]}

//Show Schema

const showSchema = new Schema({
title: {
    type: String,
    unique: true,
    required: [true, 'Title can not be empty.'],
    trim: true,
    text: true
},
slug: String,
poster_path: {
    type: String,
    required: [true, 'Cover can not be empty.'],
    trim: true
},
overview: {
    type: String,
    required: [true, 'Description can not be empty.'],
    trim: true,
    text: true
},
release_date: {
    type: Date,
    default: Date.now(),
    required: [true, 'Release date can not be empty.']
},
category: {
    type: String,
    trim: true,
    required: [true, 'Please provide category']
},
vote_average: {
    type: Number,
    min: [1, 'Rating must be 1 or above 1'],
    max: [10, 'Rating must be 10 or below 10']
},
vote_count: {
    type: Number,
    default: 0
},
cast: [
    {
        type: mongoose.Schema.ObjectId,
        ref: 'Cast'
    }
]
})

//Create slug
showSchema.pre('save', function(next) {
    this.slug = slugify(this.title, {lower: true})
    next()
})

showSchema.pre(/^find/, function (next) {
    this.populate({
    path: 'cast',
    select: '-__v'
})
next()
})

//Cast Schema

const castSchema = new Schema({
name: {
    type: String,
    trim: true,
    text: true,
    unique: true,
    required: [true, 'Please provide name of actor']
},
profile_path: {
    type: String
}
})

And this is how I did it

exports.add = async (req, res) => {
const show = {
    category: req.body.category,
    overview: req.body.overview,
    poster_path: req.body.poster_path,
    release_date: req.body.release_date,
    title: req.body.title,
    vote_average: req.body.vote_average,
    }

try {

    Cast.insertMany(req.body.cast, function(error, createdCast){
        if(error){
            console.log('Cast', error)
            return
        }
        Show.create(show, function(error, createdShow){
            if(error){
                console.log('Show', error)
                return
            }
            createdCast.forEach(element => {
               createdShow.cast.push(element._id)
            });

            createdShow.save(function(error, show){
                if(error){
                    return
                }
                console.log('saved Show', show)
            })
        })
    })
} catch (error) {
    console.log(error)
    res.status(400).json({
        message: 'fail',
        error: error
    })
}
}