Several grammar questions!?

Several grammar questions!?

"She is finished eating"
What are the functions "finished" and "eating".

"I am ready to go"
Functions of "ready" and "go"?

"I was just about to go"
Just ? About? To go?

"I want to change my order to steak"
To change? My order to steak?

"The mall is opposite to the street."
Opposite? To the street?

"My birthday is soon"
Soon?

"He may not be as dangerous as him"
As dangerous? As Him?

"You're of age to vote"
Of age?

"Swimming makes me feel great"
Me? Feel great?

"She is taller than me"
Than me?

Yeah : ) I know the meaning of all these sentences, I'm just confused about the grammar.