If you are getting notifications from WebBoostSeach, then your Mac is infected with adware. WebBoostSeach is adware for Mac.
WebBoostSeach changes setting in your Mac. First, WebBoostSeach installs a browser extension in your browser. Then, after WebBoostSeach hijacks your browser, it modifies settings in the browser. For example, it changes the default home page, modifies search results, and displays unwanted pop-ups in your browser.