How would I make a .png show up on peoples screens?

So right now this function makes a sound play when each team wins, I want to remove the sound and add a picture that says “Runners Win” so I thought the easiest way would be just to modify this.
I can’t find anything that makes a picture show up on peoples screens.

[LUA]function GM.ReceiveRoundResult( length )
local winner = net.ReadInt(4)
if winner == TEAM_RUN then
surface.PlaySound(“music/HL2_song15.mp3”)
else
surface.PlaySound(“music/stingers/HL1_stinger_song8.mp3”)
end
GAMEMODE.Winner = winner
hook.Call(“OnRoundEnd”, GAMEMODE, winner)
end[/LUA]

bump

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