Which function selector and input data should be used in solveChallenge?

I am working on the solveChallenge function which requires a function selector and input data to be passed. I am unsure about which function I should get the function selector for, and what the input data should be that needs to be turned into bytes. Any guidance on this would be greatly appreciated. Thank you in advance for your help.

function solveChallenge(bytes4 selectorOne, bytes memory inputData, string memory yourTwitterHandle) external {
 (bool successOne, bytes memory responseDataOne) = i_helperContract.call(abi.encodeWithSelector(selectorOne));
 if (!successOne || uint256(bytes32((responseDataOne))) != 1) {
 revert S1__WrongSelector();
 }

 (bool successTwo, bytes memory responseDataTwo) = i_helperContract.call(inputData);
 if (!successTwo || uint256(bytes32((responseDataTwo))) != 1) {
 revert S1__WrongData();
 }
 _updateAndRewardSolver(yourTwitterHandle);
}

I am motivated to understand how to find the solution, not just for obtaining the NFT. Thank you for your assistance.