If you have something already infected I would recommend safley backing up files and do a fresh install.
Note: Scan backed up files before moving back onto a new install.
If thats not possible for whatever reason still backup but first scan with a boot disk AV e.g Kaspersky then run another full scan with your own AV after. I would also reccomend using something like Malwarebytes as I have had good experiances with it and it comes with exploit protection.
Thats a very quick generic process but if you know specifics of what your infected with try posting on a malware removal forum such as this one.