Help needed to clean unwanted files and optimize computer

I have updated to Nortonlifelock but can no longer clean out unwanted files or do my own scan to optimise computer. Have looked online but when i go to the tools section cannot proceed any further is something missing on my norton. Getting very frustrated with norton why I can't do what I used to.

[Edit: Clarified subject]

Which product are you trying to use for this? Norton 360 or the Norton Utilities Premium?