The Lakers beat the Sacramento Kings 121-114 on Sunday night, with Kuzma scoring 18 points.
The team showed its depth with four players scoring more than 15 points in the win.
It was the first time the Lakers had won without James and Rajon Rondo, since the pair suffered injuries.
James is still recovering from a groin strain he suffered on Christmas Day against the Golden State Warriors.
Rondo, however, is set to miss a number of matches after having surgery on his arm.
The veteran is set to be out until February.
But Kuzma believes that the win over the Kings shows that the Lakers don’t always need the pair.
One of the main criticisms of the Lakers through the start of the season was the lack of depth in the roster.
However, with the Lakers forced to play without their two elder players, the young stars have had to step up.
And Kuzma explained that the young core will continue to get better.
“Just that we can do more as a young core and as a team,” he said when ESPN asked what he has learned from playing without James and Rondo.
“We are not just one player, we just got to eliminate little mistakes and we could have won all three games [without them].
“For us, it is just continue to keep getting better and better and when those guys get back, hit the ground running.”
The Lakers are next in action on Thursday, as they face the Oklahoma City Thunder.