How to Convert Image for Upload?

I want users of my website to upload images that will then be sent to S3 for storage. In order to do that I need to convert the image file to one of these types: “string, Buffer, Stream, Blob, or typed array object”

I tried:

let Image = $w("#uploadButton1").value
let ToSend = Image.blob()

But this did not work.

Does anyone have any ideas?