someone helps how can i make two for loops over a 2d array in c ( i didn't learned pointers yet )

Question

i did not understand why score [j][i] instead of score[i][j] in Sb function .Scondly i would like to know also why shall declare intialite the array named Total before the for loop and in the for loop . Finally , in the same function i would like to understand why the use of the final for loop and why we don't print the total in the first loop .
#include<stdio.h>
#include<cs50.h>
void SB(int n,int m, int score[][100]);
void remplir_mat(int n,int m, int score[][100]);
int main(void){
int N=get_int("Enter players numbers:");int M= get_int(" Enter rounds number:");
int score[100][100];
remplir_mat(N,M,score);
SB(N,M,score);
}
void SB(int n,int m, int score[][100]){
printf("SB func");
int Total[10]={0} ;
for(int i=0;i<m;i++){
Total[i]=0;
for(int j=0;j<n;j++){
Total[i]=Total[i]+score[j][i];
//printf("%d",Total[i]);
}
}
for(int j=0;j<n;j++){
printf("%d",Total[j]);
}
}

void remplir_mat(int n,int m, int score[][100]){
for(int i=0;i<m;i++){
for(int j=0;j<n;j++){
score[i][j]=get_int("enter the score of the player %i in the round %i is:%i ",i,j,score[i][j]);
printf("%i\n ",score[i][j]);
}
}
}

Answer 1

If you use score[i][j] your function will go through this array line by line, otherwise (score[j][i]) will go through it column by column.

You don't need inicialize the Total two times, just one.

Answer 2

Recommendation:
C tutorial for beginners by Bro Code:
https://youtube.com/playlist?list=PLZPZq0r_RZOOzY_vR4zJM32SqsSInGMwe&si=UXAFo3qRIqS_OTmZ