'npm' is not recognized as an internal or external command, operable program or batch file, but it's in my env path

I'm trying to launch on Windows a node.js module that I have written on Linux.

I have set the env path to nodejs, i have installed my dependencies, when i use npm alone it's working. But when I npm start my module, it's telling me this :

Here is my package.json's scripts :

Can someone explain to me what's wrong ?

Thanks in advance.

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