Please refer to Importing a Helm Chart and import the Helm chart under the Helm Chart (Catalog -> Helm Charts ) section in Nirmata.

Once the Helm chart repository is added in Nirmata, Navigate to the repository (Catalog -> Helm Charts -> «Imported Helm Chart») and select the chart version that needs to be imported in Catalog

Upon choosing the chart version a dialogue box will be displayed, enter the catalog name in Catalog and Click on Import Chart. Upon Click it will navigate to the selected catalog section and the imported helm chart will be visible under the Applications section

Refer Deploy an application to deploy an application