Can you please let us know how you installed your HDP? If you need to access Dashboard you can go to http://:8080. Once in the dashboard you can click on installed service and there you should find a link to UI for particular service. For example if you click on HDFS you will find link to NameNode Web UI which will be: http://namenode:50070, or Map Reduce JobTracker Web UI http://jobtracker:50030.
Hope this helps,