Ooh la la, on the French Riviera
He goes from detailing his relationships with Spanish girls, to those with French girls.
Ooh-la-la is a french expression of pleasure, so it is likely that Gambino is tlaking about pleasing a french girl.
This is confirmed later in the line, when he says he’s on the French Rivera, a famous coastline landmark.
To help improve the meaning of these lyrics, visit "Fire" by Childish Gambino Lyrics and leave a comment on the lyrics box