literally: 'to have one's eyes bigger than one's belly' - that means one wanted too much of something, so much that he could not handle it - or obtain it - afterwards
The phrase 'avoir le bonheur' means to have the pleasure. In the word-by-word translation, the verb 'avoir' means 'to have'. The definite article 'le' means 'the'. The noun 'bonheur' means 'delight,...