A suspicious app (probably a malware or adware) on chrome. How can I get rid of it?

Hi,

While I was tracking a package, I installed an app (packageintransit.com)by mistake onmy macbook (El Capitan 10.11.3)

Then immediately I uninstalled it but I think I did the second mistake because I used the app icon that had been added to my chrome browser to uninstall it.

Then I checked the system by "malwarebytes" that it couldn't find "any threats on the system".

I reset google chrome then. After that I searched the app name on the web and found some information that shows it's an adware and it can access to the important information on the system such as passwords.

Now I don't know what to do. all my important account passwords are saved on the browser.

Should I reinstall google chrome?

Is only Google chrome in risk?

How can I be sure if it's infected?

Should I restore my Mac os to a previous back up? It works?

Should I use an Anti virus? which one?

Or should I install a fresh copy of mac os x? This is the worst because I'll lose my VmWare and Windows and all my applications.

Please let me know what I should do now to get rid of it.

Thank you