If the file you want to download is suspicious, undo your intention to download it. Indeed there are some files such as crack files, keygen that are read by viruses and the file is needed for applications or software that requires crack or keygen to use it for free.
the most dangerous is when you start downloading the correct file but there are lots of advertisements that make you download an unknown file, usually it will have an extension. EXE and this is very dangerous. make sure the file you downloaded is correct and matches the name of the application you are looking for.
- Antivirus
Use a known antivirus (can be free but paid is better). I suggest MalwareBytes, they also have a 14 day free premium trial without credit card
Pros: Easy to download, free (if you don't get paid version)
Cons: Might take a while for the antivirus to detect your viruses and remove them, might not work with advanced viruses
Some free antiviruses such as malwareBytes are better and are able to ward off malware, ranshomeware and several other viruses. In addition there are many other types of Antivirus that can be chosen, you can see it in the link below.
The best Antivirus 2020https://sea.pcmag.com/antivirus/22/the-best-antivirus-protection-for-2020- Windows Defender
You can scan for viruses with windows defender, and you will have the option of removing detected viruses or keeping them (don't know why'd you do that)
Pros: Free, easy to use
Cons: Also might not detect advanced viruses
Windows defender became the main virus and accompanied the second antivirus that I installed. This will be safer with double protection. When Antivirus or Windows Defender is able to ward off any viruses as long as their database is always updated. It is recommended to always be connected to the internet and the database is updated at all times to secure your device.