+++Grumbler (the modern interpretation)

+++Elena (the literary/Victorian version)

Стоит сказать, что русский текст не претендует на литературность. Любой писатель, как минимум, сказал бы "отправился/направился", а не "пошел".

I can only go by the English. LEARNT in the sense of “found out” (especially instead of LEARNED) is literary. SET OUT FOR is used for epic journeys in stories (also literary) and thus in this context. The Russian sounded more casual to me too.

To me it sounds like a school student struggling with retelling/composition.
I don't understand why Russian language is so primitive.
"Пойти" можно в магазин, кино, школу неподалеку, но не в королевство.

Thank you for pointing that out. It’s interesting that it stood out even for me.

In English, however, there WOULD be one distinction. In this scenario, WENT THERE would be appropriate: “When the young merchant found out there was a price on his head, he hid out in his sister’s barn for a week. But he knew he would soon be found. His cousin brought him word that the ruler of the Kingdom of Goz offered him asylum. He found out where the kingdom was and went there.” Here, SET OUT would only refer to the formal beginning of an epic journey, but WENT would just refer to his retreat to a safe place. Could it be the same in Russian?

Я бы не сказал. Даже в этом контексте "пошел" звучит неестественно.

направился, отправился, перебрался

Aha!