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

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

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

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

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

Hope I helped!