Go
The go radical and the go kanji are exactly the same!
If you know your radicals well enough (and you do), you'll know this kanji.
こう, ぎょう
い, おこな, ゆ
None
"Oh, did he go again?" When こういち is not around, that's what people often say because he goes to the gyoza (ぎょう) restaurant almost every day. こういち just loves gyoza so much, you always know where he is when he is not home.
Remember, whenever we see the reading こう, think of こういち, a founder of WaniKani (who loves gyoza). We'll keep it consistent, so over time you should develop a character around こういち that you learn to love or hate.