I now have this code but it is still just showing a green box like first gyazo picture :O . I did check if there was something wrong with the "fear.tga" file itself and grabbed a quick icon from elvui package but that did not work either.
Lua Code:
local tec = k:CreateTexture(nil,"OVERLAY")
tec:SetPoint("RIGHT")
tec:SetSize(32, 32)
tec:SetTexture("Interface/AddOns/ownAddon/icons/fear.tga")