How to send Javascript file object to AWS Lambda function

I’m wondering how to send Javascript File object to AWS Lambda. I have a File object which collected from <input type="file"> and formed as File() object. I’m sending the File() object through an HTTP request to AWS Lambda but ended up getting undefined on the Lambda function.

Front End(Javascript)

let uploadFile = new File(
   [file], 
   Date.now() + " - " + file.name, 
   {type: file.type}
)

const body = {
   payload: {
      file: uploadFile,
      comment: "Uploading File."
   }
}

fetch(url, {
   method: "POST",
   headers: {
      "Authorization": token,
      "Content-Type": "application/json"
   },
   body: body
}).catch((err) => {
   reject(err.json());
});
                        

Back End (AWS Lambda, Typescript)

const handler = async (event: APIGatewayProxyEventV2): Promise<any> => {
   console.log("Whole Event Body:", event.body);
   console.log("Event Body Payload:", event.body.payload);
   ...
}

I’m just getting undefined from the event. I wonder am I doing it correctly? Is it possible to pass the File() object to AWS Lambda?