First you will need to navigate to Administration > System > Options using the top navigation pane.

HMRC Details & Options

The HMRC Self-Assessment, Corporation Tax and VAT online filing details, the HMRC

Agent Ids and HMRC Digital Tax Details and options are entered within this tab. You can also

enable the Get Values from HMRC (API link option) by checking the Enable SA pre-population box.

Companies House Details 

The Companies House Online Filing details can be stored on this tab. If you do not have a
Companies House Presenter ID and Authentication Code you can use the Companies
House online filing application form available as shown in the following image: