Arrays.sol

pragma solidity ^0.6.0;

contract MyContract {
    // Arrays
    uint[] public uintArray = [1,2,3];
    string[] public stringArray = ['apple', 'banana', 'carrot'];
    string[] public values;
    uint[][] public array2D = [ [1,2,3], [4,5,6] ];

   
   function addValue(string memory _value) public {
        values.push(_value);
   }
   
    function valueCount() public view returns(uint) {
        return values.length;
    }
}

The code below works fine.

 function addArray2D(uint[] memory _array) public {
      // append to array2D
      array2D.push(_array);
  }

function getArray2D(uint index1, uint index2) public view returns(uint) {
    // get element at specific index
    return array2D[index1][index2];
}