To prevent hot-linking you have different options, you can either setup your website to block hot-linking attempts, by straight up denying hot-links from your server's request. This is the simplest way of handling hot-links. You don't even have to have any tech knowledge, or know about IT or programming to do this. If you use a CDN (like Cloudflare for example), you do this by flipping a (virtual) switch, easy-peasy.
But another way, and the one that we use, albeit requiring more tech-y work, has a more fun outcome. Rather than blocking the hot-link requests, you can use a bit of programming, to deliver the image of your choice. The best part is that this only becomes visible to the hot-linker when they actually embed the image to their site.
Now we decided to use a fun and useful image (at least in terms of marketing), but trust me, I've seen quite horrid examples of images that come as a result of hot-linking attempts.
Of course this is probably not the best way to spend your time, if you're working on a website, but to be fair, knowing what the result looks like, it is a fun thing to do! :)