Oh I suggest going to Bulbapedia, and clicking the medium sized link, so watch.
From the Gogoat page, press on the official artwork. Then press on the 240 x 240 pixels link, use the insert picture option on it, and copy and paste the link. So here:
https://cdn.bulbagarden.net/upload/thumb/b/bc/673Gogoat.png/240px-673Gogoat.png