It was themy first experience tof seeing fantastic scenery which was totally different from our society.

I was required to wear fins , mask and a snorkel , then I was ready to go.

The next second I saw a lot of colorful fishes that were a variety of shapes and sizes.

a variety of + sth is a fixed pattern

Also, in my imagination of, coral was only one color which was pinky red , however in reality in the sea had not only that color, but also yellow, green and violet .

I was crazy about faceding such a marvelous and illusory world for a long time and totally forgot to check where I was floating.

As I faced up form seagot to the surface, I was in far from the first position I had started snorkeling.

"get to the surface" shows when you go from under-water to the surface of the water

When I looked around, my younger brother was in a totally different area, in order to continue for chasing pretty fishes which we have never seen before in whole our lives.

I perfectly understood that he was so hooked on snorkeling and found it so hard to leave from anthis unbelievable, untouched scenery.

So he was so excited that he forgot to think about his back, which had been burningt by sun.

or "which had been sunburnt"

Poor myMy poor brother had hadto suffer the pain of sunburn for a couple of days after this gorgeous vacation ion the tropical island.

I am looking forward to visiting an attractive place in the Caribbean for snorkeling in the near future after this pandemic ends.