Все прчинено, все работает

OOP/OOP.iml

@@ -3,6 +3,7 @@
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
     <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/Resources" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
     </content>
     <orderEntry type="inheritedJdk" />

OOP/src/Main.java

@@ -1,7 +1,4 @@
 import javax.swing.*;
-
-//TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
-// click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
 public class Main {
     public static void main(String[] args) {
         JFrame.setDefaultLookAndFeelDecorated(false);