I am having a hard time finding Routing rules and Queue topics,for my request queue, in the new experience. Can anyone point me in the right direction?

When you are in the request queue project there should be options on the left panel for Queue topics, topic groups and routing rules. If they are not there you may not have them setup to display in your layout template. You will need to go into the setup > Interface > Layout templates and make sure to turn on those options for the left panel of the project view.

Here is the documentation:

https://one.workfront.com/s/document-item?bundleId=the-new-workfront-experience&topicId=Content%2FManage_work%2FRequests%2FCreate_and_manage_Request_Queues%2F_create-manage-request-queues.htm&_LANG=en