you can create 3-digit accounts by using the "Account" module and adding the accounts manually through the user interface. To do this, you will need to navigate to the "Accounting" menu, then select "Chart of Accounts." From there, you can click on the "Create" button to add a new account. In the "Code" field, you can enter a 3-digit code for the account. Once you have filled in all of the required fields and saved the account, it will be available for use in financial transactions.

If you have a lot of accounts to create, you can also import them via CSV file, you can use the "Import" button on the top of the screen and map the columns of your CSV file to the fields of the accoun

Additionally, you can use the developer mode to create the accounts with code, by creating a new module and inherit the account model and create the accounts on the python fil