Creation of UI for Milestone 3

Hello Team
Any reference code base to create ui to display data in milestone 3. I already referred nha hiu portal but I can’t understand how to develop that ui which accepts and display pdf and other fhir data from received json. Problem is how to parse the json and display to screen, any code base sample to understand the flow will be helpful if anyone have
@Govind_Deshmukh @Gayatrij @IntegrationSupport @indrajit if you can help me on this