Hello @dmharshit
For issue 1 You must have administrative privileges to access it.
For issue 2
TezUI has become obsolete and should be disabled.
To disable the same, set tez.am.tez-ui.webservice.enable = false
In Cloudera Manager UI -> Hive on Tez -> Configs -> Hive Service Advanced Configuration Snippet (Safety Valve) for hive-site.xml