Hello, im new to java and wanted to ask a question about my code. I need to take a 4 column from massive and sort it. I have massive, but im not sure about my next steps, am i doing it right, and how should i do a sort?

My massive code

int n = 4;
int m = 56;
int a = 0;
int b = 6;
int[][] mas = new int[n][m];
for(int i = 0; i < mas.length; i++) {
for(int j = 0; j < mas[i].length; j++) {
mas [i][j] = (int)(Math.random() * (1 + b-a) + a);
System.out.printf("%2d", mas[i][j]);
}
System.out.println();
}

And here im trying to get numbers from 4 column

int col = 4;
int rez = 0;
for (int i = 0; i < n; i++)
{
rez = mas[i][col];

System.out.println();
System.out.println("4 column numbers: "+ rez);
}