Java table issue with getting average of colums

so I just started with java and my task is to make simple table filled with random numbers. Have to get each average value of rows and columns at the end of line. I did almost everything tryed to play with arrays, been calling variables out of specific loop but nothing worked, so looking for any ideas or any help i could get.

package com.company;

import java.util.ArrayList;
import java.util.Scanner;
import java.util.Random;
public class Main {

public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    System.out.print("Enter your name: ");
    String name = sc.next();
    System.out.print("Enter your surname: ");
    String surname = sc.next();;
    int name_length = name.length();
    int surname_length = surname.length();
    int a = 0; // Balses(Vowels)
    name = name.toLowerCase();

    for(int i = 0; i < name.length(); ++i){
        char ch = name.charAt(i);
        if(ch == 'a' || ch == 'e' || ch == 'i'
                || ch == 'o' || ch == 'u'){
            ++a; // Vowels
        }
    }
    int b = name.length() + surname.length();
    int rows = 4;
    int cols = 4;
    double average_rows=0;
    int average_cols = 0;
    Random random = new Random();

    for (int i = 1; i <= rows; i++)
    {   // Table
        for (int j = 1; j <= cols; j++) { // Table
            int result = random.nextInt(b - a) + a; // Making random numbers
            System.out.print(result+" ");
            average_rows += result;
            }
        if (i <= rows)
            {
            average_rows = average_rows/4;
            System.out.print(String.format("%.4f",average_rows) + "\n");
            }
        }

        System.out.println("\nName length: " + name_length + " Surname length: " + surname_length);
        System.out.println("Vowels: " + a + " Letters of name and surname: " + b);
    }
}

Specific place:

for (int i = 1; i <= rows; i++) {   // Table
            for (int j = 1; j <= cols; j++) { // Table
                int result = random.nextInt(b - a) + a; // Making random numbers
                System.out.print(result+" ");
                average_rows += result;
                }
            if (i <= rows)
                {
                average_rows = average_rows/4;
                System.out.print(String.format("%.4f",average_rows) + "\n");
                }
            }

Nailed it with rows but talking about columns feeling in dead end.

If you need the average of each cell by col, you can create another 2 for loops and just switch the rows and cols.

If you just need the average of rows of col,

for (int i = 1; i <= rows; i++){
   for (int j = 1; j <= cols; j++) { 
      // your code
   }
   average_rows = average_rows/4;
   System.out.print(String.format("%.4f",average_rows) + "\n");


   // column part of code add whatever you need to the variable totalColumn
   totalColumn += result;
}
average_cols = totalColumn /4;

Also in java, it's better practice to use camelCase than _

I'm not seeing the table visualization; looks like 2 for loops to get 2 averages using random. But if you need to store each cell, I would use a 2d array.

Also

if (i <= rows)

Is not necessary because it will always run, since it's inside

for (int i = 1; i <= rows; i++)