Created using remix-ide: Realtime Ethereum Contract Compiler and Runtime. Load this file by pasting this gists URL or ID at https://remix.ethereum.org/#version=soljson-v0.8.7+commit.e28d00a7.js&optimize=false&runs=200&gist=

contracts...StorageFactory.sol

// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.3;
import "./SimpleStorage.sol";

contract StorageFactory is SimpleStorage{
    SimpleStorage [] public SSArray;
    function createSSContract()public{
        SimpleStorage genSS=new SimpleStorage();
        SSArray.push(genSS);
    }

    function sfStore(uint256 index, uint256 age) public {
        SimpleStorage(address(SSArray[index])).incrementAge(age);
    }

    function sfGetAge(uint256 index) public view returns (uint256) {
        return SimpleStorage(address(SSArray[index])).getAge();
    }

}