When Google Image Was Click It Was Redirected With Ads

I discovered that some of my images on my website was used by other website, and when I tried to click their site on google, they were ads. I tried to click the images, it was an ads. How do they do it? For sure, it was not Adsense because they will easily get blocked. Not sure what it is though. What do you think guys, they were using?

You can hyperlink the images, I do the same with clickbank

Can you do that with pay per click ad network such as Adsense?

Also can you insert a link on images on website? Adsense