Adding an external URL when clicking an image with the rich text editor of Sanity

I'm trying to make possible for the people using the rich text editor in sanity.studio (with no coding knowledge) to add an external link in the image they are uploading. So, then it is clickable in the post they are adding and take the user to another page. Right now they are only able to add some ALT text and edit the picture. This is the code about the images in the blockContent.js:

{
type: 'image',
fields: [
{
type: 'text',
name: 'alt',
title: 'Alternative text',
description: `Some of your visitors cannot see images,
be they blind, color-blind, low-sighted;
alternative text is of great help for those
people that can rely on it to have a good idea of
what\'s on your page.`,
options: {
isHighlighted: true,
hotspot: true,
},
}
],
}