Virus hoaxes are also dangerous, although they are technically just hoaxes/fake. These types of viruses are harmless but can cause people to ignore actual viruses.

A while ago there was a steam game that was a pretty simple and neat platformer. The problem was however, that the game made GPUs (graphics processing unit) and CPUs (central processing unit) struggle to keep up. After a while it was discovered that the game actually hijacked computers to farm cryptocurrency.

Although it is recommended to load a backup if your computer gets infected, personally I believe the only way to truly delete/remove every virus is to buy a new hard drive/ssd. However most of the time a reformat will do wonders and at least speed up your computer. If you plan on transferring old files, try to only bring what is absolutely necessary as viruses can be hidden amongst normal programs. Also most importantly, don't click on unknown links or links from unknown sources (links can be edited to show another website). Never download anything from untrustworthy sources. Be careful of random USB sticks that you might find or ones that you receive. Ignore any email that appears to be a scam.