Java, Best way to make and place a loop for enemy waves in a game

I am working on a OOP final project which is a text based survival game. I am currently trying to finish it up by having the player enter how many enemies they would like to fight then it loops through it until the amount is met. What would be the best route? I want it so that enemies can be selected twice, but my partner wants to do a shuffle of the array because less work.

Mostly I am stuck on where and what kind of loop I should make and where should I place it.

This is some code in the main class.

Entity entity = new Entity();
        ArrayList<Entity> enemies = new ArrayList<>();
        EnemyList enemyList = new EnemyList();

        Entity troll = new Troll();
        troll.setName("Troll");
        enemyList.characters.add(troll);

        Entity imp = new Imp();
        imp.setName("Imp");
        enemyList.characters.add(imp);

        Entity knight = new Knight();
        knight.setName("knight");
        enemyList.characters.add(knight);

        Entity skeleton = new Skeleton();
        skeleton.setName("Skeleton");
        enemyList.characters.add(skeleton);


        Integer[] array = new Integer[enemyList.characters.size()];
        for (int i = 0; i < array.length; i++) {
            array[i] = i;
        }

        Collections.shuffle(Arrays.asList(array));


 for (int i = 0; i < enemyCount; i++) {

            for (Entity someEnemy : enemyList.characters) {

                System.out.println(enemyList.characters.get(array[i]));

                System.out.println(someEnemy.getName(entity) + "\n");
                System.out.println("A " + someEnemy.getName(entity) + " Appears! It has " + someEnemy.getHealth() + "HP");

                while (someEnemy.getHealth() > 0) {

                    int attack = character.getAttack();
                    System.out.println("You hit the " + someEnemy.getName(entity) + " for " + character.getAttack());
                    int monsterTotalHealth = someEnemy.setHealth(someEnemy.getHealth() - attack);
                    System.out.println(someEnemy.getName(entity) + " has " + monsterTotalHealth + "HP Left");
                    System.out.println("");

                    if (someEnemy.getHealth() > 0) {

                        System.out.println("The monster attacks back for " + someEnemy.getStrength());
                        int remainingHP = character.damageDelt(someEnemy.getStrength());
                        System.out.println("Your remaining health is " + remainingHP);
                        System.out.println("");
                        character.setHealth(character.getHealth());
                    }

                    if (character.isDead()) {

                        System.out.println("You have been defeated!");
                        System.exit(0);

                    } else if (someEnemy.getHealth() < 0) {
                        System.out.println("Fighting Next monster");

                    }

                }
            }

        }

Entity class

public class Entity {

    private String name;
    private int health;
    private int level;
    private int vitality;
    private int strength;
    private int resistance;
    private int dexterity;
    private int endurance;
    private int intelligence;
    private int attack;

    public String getName(Entity someenemy) {
        return name;
    }

    public int getHealth() {
        return health;
    }

    public int getLevel() {
        return level;
    }

    public int getVitality() {
        return vitality;
    }

    public int getStrength() {
        return strength;
    }

    public int getResistance() {
        return resistance;
    }

    public int getDexterity() {
        return dexterity;
    }

    public int getEndurance() {
        return endurance;
    }

    public int getIntelligence() {
        return intelligence;
    }

    public int getAttack() { return attack; }

    public void setName(String name) {
        this.name = name;
    }

    public int setHealth(int health) {
        this.health = health;
        return health;
    }

    public void setLevel(int level) {
        this.level = level;
    }

    public int setVitality(int vitality) {
        this.vitality = vitality;
        return vitality;
    }

    public void setStrength(int strength) {
        this.strength = strength;
    }

    public void setResistance(int resistance) {
        this.resistance = resistance;
    }

    public void setDexterity(int dexterity) {
        this.dexterity = dexterity;
    }

    public void setEndurance(int endurance) {
        this.endurance = endurance;
    }

    public void setIntelligence(int intelligence) {
        this.intelligence = intelligence;
    }

    public void setAttack(int attack) {
        this.attack = attack;
    }


    @Override
    public String toString() {
        return "This enemy is appearing: " + name  +
                ", health is " + health +
                ", strength is " + strength;
    }
}

EnemyList class

import java.util.ArrayList;
import java.util.List;

public class EnemyList {

    List<Entity> characters = new ArrayList<>();

    public void print()
    {
        for (Entity entity : characters)
        {
            System.out.println(entity.toString());

        }
    }

}

Mechanics Interface

interface Mechanics {

    boolean isDead();

    int damageDelt (int damage);

    //int levelup();


}