This paragraph actually means that the output path is not specified, because you did not create a new module after creating the project in idea, but directly created a java file under src and ran it.
I use IDEA 2022.1 myself
Use this to show how to solve the problem
First, right-click on the IDEA project
Click to open the module settings in the pop-up tab
Select the project column in the opened interface
Select your jdk in the SDK column
Then find the directory of your project in the compiler output column, create an out folder in the directory, and enter the path to this folder.
After the change is completed, it can run normally!
Please give it a like if it is useful, your support is my biggest motivation!
o(*▽*)q