It is a final particle to express "indeed this is so". Other meanings can be, casual reminder, connoting a sense of expectation [wo3] or surprise [wo4]; sometimes used to report second-hand information [wo5] Here's a good Cantonese resource link http://www.cantonese.sheik.co.uk/dictionary/

It's a final particle and used to emphasize something. 好好食喎 means it's so delicious so 喎wo is used to emphases how delicious it is For example, 套戲好好睇喎！tou3 hei3 hou2 hou2 tai2 wo! This movie is so GOOD! Alternately, you can use 呀(ar) to emphasize something For instance, 佢好靚仔呀！keoi5 hou2 leng3 zai2 ar! (He is SO handsome!) Feel free to send me a message regarding Chinese or visit elainelanguages.com

Auxiliary word