Whoat is a Manatiee?

MA manatiee is a marine mammal.

Most of the time it just eats some sea grass , watches people on the shore from thea safe distance, or very quietly sings its melodic sea songs.

Deleting extra words and adding a comma helps the reader hear the cadence of the sentence.

People say that you can see your destiny if you look at Min a manatiee's eyes.¶
People say that you can see your destiny if you look a manatee in the eyes.

Both of these are common idiomatic expressions. They imply some kind of understanding between living beings.

Looking "at" something is used mostly with places (look at the view, the mountains) and nonliving subjects (look at the building, the floor, the TV).

So be careful, and don't swim close, as some things are better remainleft unknown.

Certain commas are required by grammar rules. Sometimes they are optional, and the writer can use them to show which phrases go together and where to pause briefly and maybe take a breath.

Whoat is a Manatiee?

You normally say "who" for individual people. If you're talking about an individual domesticated manatee, you could use "Who", but not when talking about the species over all

MA manatiee is a marine mammal.

Most of the time it just eats some sea grass , watches people on the shore from thea safe distance or very quietly sings its melodic sea songs.

People say that you can see your destiny if you look at Ma manatiee's eyes.

So be careful and don't swim close as some things are better remainleft unknown.

"to leave unknown" has more of a sense of intentionality than "to remain unknown" and so when you're giving people advice on how to act, it's better to use "leave unknown" (or left unknown as the tense is here)