You cannot give someone courage, but sometimes your presence is all a person needs in order to behave courageously.
They simply need to know, whether they win or lose, succeed or fail, that you will be by their side throughout the experience.
The work of being courageous is theirs alone to do, but your presence can be a platform upon which they stand when they do that work and upon which they fall if they fail.
In this way, in the truest sense of the word, your presence is an act of encouragement.
That is to say, your presence has the ability to give someone courage they may not have been able to tap into alone.