This is Example Code How To Make Collectionview Used Dynamic Height From this answer https://stackoverflow.com/questions/45204283/collectionview-dynamic-height-with-swift-3-in-ios

collectionview-dinamic-height.swift

//
//  TestimonyCollectionViewController.swift
//  EMtrade
//
//  Created by Fachruzi Ramadhan on 02/09/20.
//  Copyright © 2020 Fachruzi Ramadhan. All rights reserved.
//

import UIKit

class TestimonyCollectionViewController: UICollectionViewController, UICollectionViewDelegateFlowLayout {
    
    private let reuseIdentifier = "Cell"
    
    //var testimonyList = [String]()
    var testimonyList = [
        ["profile": "testimony_maryati", "testimony": "Sejak bergabung dengan Premium Access dari Ellen May Institute, invetasi saya bertumbuh. Saya berusia 47 tahun, mulai berinvestasi saham dengan menyisihkan gaji dan uang bulanan dari suami. \n Selama satu tahun berinvestasi, empat dari saham saya masing-masing menghasilkan keuntungan 90%, 130%, 300%, dan 700%. Memang, ada pula saham-saham yang sempat merugi, tetapi investasi saya secara keseluruhan menghasilkan keuntungan. Saya menyadari bahwa ada strategi untuk meminimalkan resiko dalam investasi di saham. Karena itu, saya berlangganan Premium Access dari Ellen May Institute. Hal ini sangat membantu saya dalam memilih saham yang akan saya beli.\n- Maryani"],
        ["profile": "testimony_imam", "testimony": "Premium Access by Ellen May Institute banyak membantu saya. Dengan mengikuti arahan dari Premium Access, beberapa saham saya untung di atas 100 persen. Alhamdulillah, dalam setahun ini saya bisa menarik dari rekening dan memberli rumah Rp. 1M sementara nilai saham masih sama seperti modal.\n-Imam Edy Suwito"],
        ["profile": "testimony_mian", "testimony": "Saya semakin jatuh cinta dengan trading ini. Di sela kesibukan saya sebagai dokter, walaupun saya trading dengan cara curi-curi waktu, ternyata bisa profit juga berkat bantuan Premium Access dari Ellen May Institute. Profit saya seminggu dari trading setara dengan gaji saya sebulan sebagai dokter.\n- Mian Pasaribu"],
    ]
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        collectionView.backgroundColor = .white
        collectionView.allowsSelection = true
        
        if let layout = collectionViewLayout as? UICollectionViewFlowLayout {
            layout.minimumLineSpacing = 0
            layout.minimumInteritemSpacing = 0
            layout.estimatedItemSize = CGSize(width: collectionView.frame.width, height: 400) //530
        }
        
        collectionView.showsHorizontalScrollIndicator = false
        collectionView.showsVerticalScrollIndicator = false
        
        // Uncomment the following line to preserve selection between presentations
        // self.clearsSelectionOnViewWillAppear = false
        
        // Register cell classes
        self.collectionView!.register(TestimonyCollectionViewCell.self, forCellWithReuseIdentifier: reuseIdentifier)
        
        // Do any additional setup after loading the view.
    }
    
    // MARK: UICollectionViewDataSource
    
    override func numberOfSections(in collectionView: UICollectionView) -> Int {
        return 1
    }
    
    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return testimonyList.count
    }
    
    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier, for: indexPath) as! TestimonyCollectionViewCell
        cell.profileIV.image = UIImage(named: testimonyList[indexPath.item]["profile"]!)!
        cell.testimonyLb.text = testimonyList[indexPath.item]["testimony"]
        return cell
    }
    
    override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        
    }
    
    func getHeightForLable(labelWidth: CGFloat, numberOfLines: Int = 1, labelText: String, labelFont: UIFont) -> CGFloat {
        let tempLabel: UILabel = UILabel(frame: CGRect(x: 0, y: 0, width: labelWidth, height: CGFloat.greatestFiniteMagnitude))
        tempLabel.numberOfLines = numberOfLines
        tempLabel.text = labelText
        tempLabel.font = labelFont
        tempLabel.sizeToFit()
        return tempLabel.frame.height
    }
}

class TestimonyCollectionViewCell: UICollectionViewCell {
    
    let profileIV: UIImageView = {
        let iv = UIImageView()
        return iv
    }()
    
    let testimonyLb: UILabel = {
        let lb = UILabel()
        lb.textAlignment = .center
        lb.font = UIFont(name: "Prompt-Regular", size: 14)
        lb.textColor = UIColor(red: 0, green: 0, blue: 0, alpha: 1)
        lb.numberOfLines = 0
        return lb
    }()
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        
        contentView.addSubview(profileIV)
        profileIV.snp.makeConstraints { (make) in
            make.centerX.equalToSuperview()
            make.top.equalTo(contentView).offset(5)
            make.height.equalTo(100)
            make.width.equalTo(100)
        }
        
        contentView.addSubview(testimonyLb)
        testimonyLb.snp.makeConstraints { (make) in
            make.centerX.equalTo(contentView)
            make.top.equalTo(profileIV.snp.bottom).offset(20)
            make.leading.equalTo(contentView).offset(30)
            make.trailing.equalTo(contentView).offset(-30)
            make.bottom.equalTo(contentView).offset(-40)
        }
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
        setNeedsLayout()
        layoutIfNeeded()
        
        let size = contentView.systemLayoutSizeFitting(layoutAttributes.size)
        
        var frame = layoutAttributes.frame
        frame.size.height = ceil(size.height)
        
        layoutAttributes.frame = frame
        
        return layoutAttributes
    }
}

Autoloayout i'm used http://snapkit.io/docs/