In the Movie Boruto sensed that someone surrounded him so he used kunai to throw in different directions, then they brothers came out of their hiding spots which he pinpointed by sense alone (Idk what it is called, ninja sense or some shit?).I think it was 6 vs 5 in the novel, he got beaten and had no choice but to use the device
Was he alone in the movie? He didn't make kagebushin?
The brothers came out (3 of them) and Boruto created 3 or 4 clones. It was either 3 vs 3, or 3 vs 4 (four being Boruto).
Then the brothers each used the shadow clone jutsu making 3 each resulting in 9. So it was basically 2 vs 1 for each clone adding a few that ganged around.