Bonsoir
'Mon portrait chinois' is a description of yourself through a comparison with either animals, places, famous people, food, fruits.. anything ..... with a justification..
In English, you call it " My Chinese portrait", I think
example
si j'étais un animal je serai un chat parce que je pourrais dormir toute la journée
If I were a colour, I would be black, because it's the colour of mystery
anything you want to compare with to describe your personality
It's a way in French or English, to know if you use the conditional tense correctly....
hope this helps ;