Windows has .msi files that are Microsoft installers. Various Linux distros have a corollary, and in the case of Debian-based distros (Debian, Ubuntu, Mint, gOS, etc) that extension is deb. You can often find a deb version of the software, but it may be packaged by a third-party. If you cannot find a deb file, then the forums can help you install almost any extension.
However, since you used Avast as an example, I hope that you understand that such a software is superfluous, at best, in Mint. Mint has its own antivirus software, but people rarely use it. Virus threats on Linux are not like virus threats on Windows, so you will have two problems: first, the software will incorrectly label files as viruses and second, you will never need the software.