Do i need constructor in an abstract class?

Question

I can't understund for what is constructor in abstract class, because as far as I can understand properties in abstract class, that i can overide, i can't get point of creating construcor...

Correct me if i'm wrong - Abstract classes inform what should be declared in the derived class.

I wrote the code like below, shoud i remove constructor from abstract class and is constructor in derived class is enough? How to create object of Player class? Shoud i code: Actor player = new Player(); or Player player = new Player(); or something else? :) (I know the access modifiers are bad, but it's not a point of my study)

  {   
        //Actor.cs
        public abstract class Actor
        {
            public abstract Dictionary<int, int> ActorPosition { get; set; }
            public Actor()
            {
    
            }
        }
    }
    
     

{
    //Player.cs
    public class Player : Actor
    {
        public override Dictionary<int, int> ActorPosition { get; set; }

        public Player()
        {
            this.ActorPosition = new Dictionary<int, int>();
        }  
    }
}

    //Program.cs
    Map map = new Map(5, 10);
    
    Actor player = new Player();
    
    
    
    map.printBoard(4, 3);
    
    
    Console.WriteLine(player.ActorPosition.Values.ToList().IndexOf(0,0));