WhatsOrder can display your product images in the menu. It will also pop up to a large image when clicked. Preferably the image should be around 300px in width and be in JPG or PNG format. Images with light background looks real good. For faster load, please prefer to keep the image file size less than 500KB. You can use online tools (https://bulkresizephotos.com) to bulk resize images.
It should be direct public link to the image (not to any page).
To be able to add your product images to your website you need to host them somewhere. Here are some options:
The easiest way is just to find some images in Google Images, select image that you like make a right click and select Copy image address
Imgur is a platform where people share images.
Here is a link to a help video on using Imgur:- https://youtu.be/_VBCPt-wJ2w?t=60
ImgBB is a free hosting that you can upload your image and use on your website.
Tinyimg is another free hosting that you can upload your image and use on your website. Simply upload your image and get a direct public image link. We are not sure how long will they store the images on their website. Please proceed with caution.
Google Drive lets you save images. However they are not public URLs. You can utilize a trick to make the images public.
Here is a quick video for the same.
Tool to help change the public image link of Google drive into an usable direct public image link. Click here