Segmenting Customers

I created a test marketing list and decided I want to delete the list. I’m unable to find an option to perform the delete of the marketing list. Anyone have any idea how to delete the unwanted marketing list? Thanks

We created a 6 week journey for new contacts. Additionally new segments for every 7 days (see attached). Will these segments update automatically or do we need to manually resave each segment to update the contacts entered into the segment? Does any of this require updating the customer journeys? Looking for automation. Thanks in advance.