Player:ShowProfile
Example
Frame with all players and when click on it open Steam Profile.
local frame = vgui.Create( "DFrame" )
frame:Center()
frame:SetSize( 300, 100 )
frame:SetTitle( "Show Steam Profile" )
for i, ply in ipairs(player.GetHumans()) do
local addbutton = vgui.Create( "DButton", frame )
addbutton:SetPos( ( i * 75 ) - 50, 50 )
addbutton:SetSize( 75, 20 )
addbutton:SetText( ply:Name() )
addbutton.DoClick = function()
ply:ShowProfile()
end
end