Asking for help

I was playing a game on a server then sudenly it downloaded me a fyle that i can not find but i saw it and thought it was an error from the game.The next day i booted my pc and things were fine then crome opened to a add fly link. Thinking of this i did full scan on avast and a full boot scan but there where no results.Now every time i boot the pc the add fly link opens on me and the game i play have strange files…i delete them but the next time i boot the pc they are again there. Please help me how do i find this program since is now malicious as of avast result

Thinking of this i did full scan on avast and a full boot scan but there where no results.
If you run a full scan there is no need to run a boot scan, it does not give any better detection
Please help me how do i find this program [b]since is now malicious as of avast result[/b]
And what does avast say?

If you suspect infection and want a check, follow instructions here >> https://forum.avast.com/index.php?topic=194892.0

Thank you it worked!