Hi Delta Accounting Consultancy Firm, 

To create a new group of chart of accounts you need to first start the debug mode and follow the below steps

1) Go to Accounting > Configuration > Account Groups

2) Here You can create the Account groups by adding 'Code Prefix Start', 'Code Prefix End' and define the name of the group 

In case of more help you can reach to us.

Thanks & Regards,

Email:   odoo@aktivsoftware.com           

Skype: kalpeshmaheshwari