Explain the difference between 1st, 2nd, 3rd, and 3rd Omnipresent.

First person is when you use terms like I and me.
"I went to the store to buy milk."

segundo person is when you using terms such as you.
"You went to the store to buy milk."

Third person is using he or she.
"He went to the store to buy milk."

Omnipresent is like third person, but you are describing everyone thoughts.
"He went to the store to buy leite and she thought it was a way to get out of chores."

Hope I helped!