I did not under stand a word please help me

ABOUT THE POEM:

meaning:
It's pretty clear that "The Tale of Custard the Dragon" is a poem that basically doesn't have any deep underlying meaning, and is purely to be taken at face-value, as a children's story.
Of course the story does have a certain message. Custard saw himself as a cowardly dragon, and was even teased about it by his friends. When push came to shove, Custard was the bravest of them all when he defended his friends from the mean pirate. In the end his friends thank him, and acknowledge his courage. Custard didn't think he could be courageous, but he found out he could.

Hope it helps.