To configure Dolphin go to Settings, Configure Dolphin and on View Modes
you can change the settings for the various views. Under General, you can
have one setting for all folders or have it remember different settings for
each folder. If you like only one view, then change this to Use Common
Properties...

Then in Dolphin (not the settings) when in a folder that you want to view,
go to View, View Mode and change it to Details. Or press Control+2 to
change it with a hotkey. You use Alt+. to show hidden files and folders.