As I can see from the screen you posted you have your own “VariableWorklab” BP but the level uses the default ThirdPersonCharacter BP so it makes sense why the ‘E’ key won’t work.
If you want to use VariableWorklab, then delete the default ThirdPerson BP from the level and drag n’ drop VariableWorklab into the level instead.
You can just do on begin play -> “enable input” because your blueprint wouldn’t have had input enabled by default so pressing the E key wouldn’t do anything. You should be able to test this by watching it during debugging.