Hi folks. I'm trying to run through the first tutorial " Create an OpenAPI Specification ". When I try to start the server with $node index.js, I'm getting the error

Unexpected token 'index.js' in expression or statement.At line:1 char:15+ $node index.js <<<<  + CategoryInfo  : ParserError: (index.js:String) [], ParentContainsErrorRecordException  + FullyQualifiedErrorId : UnexpectedToken

I'm not very experienced with node.js. I copied the code for index.js directly from the tutorial. Any help? Thanks!