<img src="https://i.stack.imgur.com/g25LK.jpg" alt="The red arrows marks the abbreviations"> I have tried and googled without finding the way to remove the abbreviations. I'm also new to IntelliJ. Any help is appreciated!

You have installed Advanced Java Folding plug-in which does exactly what you see, folds and abbreviates certain language constructions. Either uninstall/disable the plug-in or configure its options according to you personal preferences: <img src="https://i.stack.imgur.com/BYYDS.png" alt="advanced folding">