Today, March 11th, 2021, ten years have passed since "The 2011 Earthquake off the Pacific cCoast of Tohoku Earthquake."

Using quotes and capital letters here is a little strange. It does make it clear that you're talking about a famous event, but you could just say "have passed since the 2011 earthquake off the Pacific coast of Tohoku."

If you do want to do something like this, English likes you to capitalise every noun in a "title" or "proper name" like this. So Coast. Some people would also capitalise Off, The, Of, but that's style and it varies.

In Nagoya, the earthquake was non't terrible, so I only watched or heard the news aboutknew how big the disaster was in the Tohoku region by watching and hearing the news.

More natural.

Now, I live in Sendai, whereich is a major city in Tohoku, and I've visited devastated areas several times.

There are many reconstructed areas, but there areis also vacant lands because ofland that is still vacant after the tsunami.

More natural again. "still" makes it clear that you're talking about how it is surprising that the land is vacant, so many years after the event.

"Land" is uncountable here.

The ten years awere so long that I have learned a lot and I changed where I live orand what I think.

"or" is a little strange here.