These two verses came from 李白 (Li Bai)'s poem
Jinling: Today's Nanjing City , Jiangsu Province, China
子弟(sons): Refers to 'native sons of Jinling' -- Li Bai's friends
'欲行' (about to leave) refers to 'the person who was about to leave'. And that person was Li Bai himself.
'不行' (not leaving) refers to 'the people who were not leaving'. And they were Li Bai's friends.
盡觴: drink down the whole cup of wine. Also refers to the cheers
" The native sons of Jinling (my friends) came to see me off; I, the one who is about to leave, and my friends who are not leaving, all drunk down a cups of wine (before we part). "