In order to get a response more "tailored" to your needs, it would have helped to know something about your system. And which security software is presently installed.

A lot of members seem to find Malwarebytes' Anti-Malware and/or SUPERAntiSpyware Home Edition, do their intended job very well. Both come in free versions. And both come in paid versions. The paid versions, would afford you real-time protection. (They are far from the only ones)

You also might want to make use of the search function, at the top of the forum. The question has been asked before. The results should afford you many and varied opinions.

Best of luck..