Google's John Mueller was asked if adding images to your web pages, if that will help you rank higher in Google Search. John said no, he said on Twitter "there is no automatic effect from adding images."
Of course, people mind find the page more engaging and welcoming if there are relevant images. Those people might share and ultimately link to the page. So there may be an indirect way of boosting your rankings by adding images.
But Google does not have a ranking algorithm that says if there is an image on this page, rank it better in web search.
Of course, the image might also rank in image search and drive some traffic for you.
This is similar to John saying adding videos to your pages do not help you rank higher in web search.
There is no automatic effect from adding images.
— 🍌 John 🍌 (@JohnMu) May 2, 2021
Forum discussion at Twitter.
Absolutely. And if your pages are shown in places like Discover, the preview image can play a big role in how attractive your page looks & how users click through to your content (also consider large image previews :-)). It's not a ranking factor, but it can affect traffic.
— 🍌 John 🍌 (@JohnMu) May 5, 2021