The easiest way to send an original photo to someone on WhatsApp is to convert it to a document and then send it.
For this, first open the WhatsApp chat. In the next step, click on the clip sign and select the document option, after which the non-image file will open in front of you.
Now you have to choose the option of Browse Other Docs, after that select the photo you want to send in original quality and send it. This way you can send photos in original quality to the receiver.