I can see you had a great conversation with @Precious. Allow me to jump in to this thread.
The steps provided help you to fix the opening balance. On the other hand, with regards to creating a contra account (details of the account), it'd be best to consult your accountant. They are the best source of help for any accounting advice. Then, we can guide you how to create it.
We can also get some pieces of advice from other users in this forum. Let's see what would their opinion be about this.
If you have other questions, please don't hesitate to post them here.