Keep your browsers and softwares up-to-date. And do not use cracks and pirated softwares!
For your browser, you need
µBlock to block ads in the browser and
HTTPS Everywhere to make your connections secure. These two extensions are essential and available for your browser. And you can use
LastPass Password Manager which saves your passwords and gives you secure access from Chrome.
You can use
CCleaner for cleaning and optimizing your PC. It is more than enough.
You can use
HitmanPro and
Malwarebytes Free as a stand-alone malware scanner. These two will not conflict with Kaspersky. If you use USB often, maybe you should consider to use
MC Shield USB Anti-Malware Tool. All these softwares are free!
Thanks for sharing