Q: got a virus and lost safari

There are no viruses that affect the Mac.

Close safari, then open again and all will be well.

1. Force Quit Safari .

  Press command + option + esc keys together at the same time.

  When Force Quit window appears, select  Safari .  Press Force Quit button at the bottom of the window.   

2. Relaunch Safari holding down the shift key.

Look in the Applications folder, you likely removed it from the Dock. Once you have found it in the Applications folder click the icon and then drag it back to the Dock. Please familiarize yourself with Mac Basics: The Dock holds your favorite apps, documents, and more - Apple Support