I mistakenly added ccleaner as a browser and then realised my mistake and went back to chrome as default. However, some files are still visible as ccleaner files (for example some photos). I don't want any photos to open via ccleaner. How do I rectify this and if I completely uninstall ccleaner as a browser what will those files open in? I don't want to lose them. Thanks for any advice.
The install of CCleaner browser has changed some of your file associations, so their icons now show the ccleaner logo and if you double click them they will open in the CCleaner browser.
Most browsers will do that during the install, unless you specifically tell them not to.
If you don't want them to open in the browser then you simply have to reset the associations for the affected filetypes back to whatever app you do want them to open in.
See this post for how to do that:
https://community.ccleaner.com/topic/57890-don/?tab=comments#comment-318193