Answer 1

As this stands, it does not belong here so I marked it for automatic deletion in 24 hours.

Answer 2

Do you mean 2 dimensional array or what?

Answer 3

If you mean a 2d array in C++ this is very simple and explained in C++ tutorial in sololearn.
https://www.sololearn.com/Play/CPlusPlus
The input is already explained in the following links:
https://www.sololearn.com/Discuss/164248/c-arrays-and-cin/
https://www.sololearn.com/Discuss/248504/how-to-input-arrays

The following link , in a comment, contains your answer.
https://www.sololearn.com/Discuss/688086/how-to-input-a-matrix-using-arrays
Your answer in the comment is:
int matrix[n_columns][n_lines];
for (size_t i = 0; i < n_columns; ++i)
{
for (size_t j = 0; j < n_lines; ++j)
{cin >> matrix[i][j];}
}

But please, for your next question use search bar. It's very easy to find already answered questions. Thanks and happy coding!