Momofuku Ando、, 安藤百福 is the person who invented instant ramen. Momofuku Ando, 安藤百福 is the person who invented instant ramen.

I would be consistent with your name ordering - in the title you use the Japanese order, "Ando Momofuku", but here you're using the English order. Generally the trend with Japanese names is to change it to the English order, though there are a few Japanese people (like Natsume Soseki) whose names use the Japanese order.

He was the founder of Nissin Foods and devoted himself to developing food products, even sacrificing sleep (to do so). He was the founder of Nissin Foods and devoted himself to developing food products, even sacrificing sleep (to do so).

Works fine as it is, but "to do so" sounds a little better to me.

At one point, he fell into debt and was left with only his house as his only remaining asset. At one point, he fell into debt and was left with his house as his only remaining asset.

After the war, he saw long lines at ramen stalls and the happy faces of people eating ramen. After the war, he saw long lines at ramen stalls and the happy faces of people eating ramen.

This line reminds me: I think I had to read a passage about him in my Japanese textbook when I was studying Japanese at university.

He immersed himself in researching instant ramen, but struggled for a long time to create something truly delicious. He immersed himself in researching instant ramen but struggled for a long time to create something truly delicious.

This is again the compound sentence construction, where two phrases or clauses are joined by a conjunction ("but"). In this case, "He immersed himself in researching instant ramen" is an independent clause, meaning that it can stand on its own as a complete sentence. However, "struggled for a long time to create something truly delicious" is not a complete sentence on its own, so it is not an independent clause. Therefore, you do not need a comma before "but."

When hot water iwas poured over them, it would enters those holes and brings the noodles back to a soft texture. When hot water was poured over them, it would enter those holes and bring the noodles back to a soft texture.

Not too major (this would probably go past undetected by most people) but good to keep your tenses consistent through the paragraph.

This is how instant noodles became known around the world. This is how instant noodles became known around the world.

The sentence is correct, but the paragraph before this sentence talks about how instant noodles were invented, not how they became famous. Maybe "And after that, instant noodles became famous around the world" or something along those lines? Or "This is how instant noodles were invented".