Add a Program for doubly Linked List in cpp

[AvinashUmrao]

This C++ program implements a doubly linked list with a Node class, allowing for the insertion and deletion of nodes at various positions. It includes functions to print the list, get its length, and manage nodes efficiently, demonstrating basic operations on a doubly linked structure.

[AvinashUmrao]

@Ayush7-BIT
Sir Please assign this issue to me
also add hactoberfest labels

[AvinashUmrao]

@Ayush7-BIT
I have created a PR

[Ashu-Viron]

I'm interested in this issue, plz assign this issue to me

[Smrn-prydrshini]

I'm interested please assign this to me.

[student-ankitpandit]

Hey @Ayush7-BIT, I am interested in the issue can you assign this issue to me.