Code:

#include <stdio.h>

void main()
{

    int a[10][10],b[10][10],i=0,j=0,s[10][10],r,c;
    printf("Enter row & column size:");
    scanf("%d%d",&r,&c); // Row & Column size will be same for Matrix Addition
 
    printf("Enter 1st matrix elements:");
    for(i=0;i<r;i++){ // Loop For Row 
        for(j=0;j<c;j++){ // Loop For Column
            scanf("%d",&a[i][j]); // Reads First Matrix
        }
    }

    printf("Enter 2nd matrix elements:");
    for(i=0;i<r;i++){   // Loop For Row
        for(j=0;j<c;j++){ // Loop For Column
            scanf("%d",&b[i][j]); // Reads Second Matrix
        }
    }
    
    // Adding the Matrices
    for(i=0;i<r;i++){
        for(j=0;j<c;j++){
            s[i][j]=a[i][j]+b[i][j];
        }
    }

    for(i=0;i<r;i++){
        for(j=0;j<c;j++){
           printf("%d\t",s[i][j]); // Prints the resultant matrix
        }
        printf("\n"); // This will helps to print the elements row-wise
    }
}

Algorithm:

Will be updated