By default, OncloudERP will create four Primary groups such as

Liabilities, assets, incomes, and expenses with four temp ledgers for each.

 User can categorize the list of the main group, sub groups, and ledgers by clicking the add button. 

The tree view of ledgers can be created in the Chart of Accounts. 

The add button will be pop up while cursor over the primary groups.

To check this at demo.onclouderp.com > Account > Setup > Chart of Accounts