No problems have been detected in the workspace so far Java Script Code

Question

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I will make a reservation in advance that I am a beginner on the path of programming, please consider that I am still inexperienced in this matter, and use a simple language, if it is not difficult for you. Thank you in advance.

Now to the crux of the matter. When writing the initial value declaration lines, Visual Studio Code does not show errors where they should be. (Startup code selected, language selected Js, after recording saved and command Startup code pressed). I tried various manipulations, the result is the same. If it is, or how to fix the error? The second day did not advance in the answers.