Using Governor Contract how I can I encode this function?

I am using OpenZeppelin governor contract through which I want to pass an encoded function to the vault smart contract function:

 function submitTransaction(address _owner, address _to, uint _txIndex, uint _value, bytes memory _data) public onlyGovernance {
        
        require(hasRole(CUSTODIAN_ROLE, _owner), "only custodians can submit transaction!");

        transactions.push(Transaction({
            to: _to,
            value: _value,
            data: _data,
            daoApproval: true,
            executed: false,
            numConfirmatons: 0
        }));

        emit SubmitTransaction(msg.sender, _txIndex, _to, _value, _data);
    }

function executeTransaction(uint _txIndex) public onlyCustodian txExists(_txIndex) notExecuted(_txIndex) {
        Transaction storage transaction = transactions[_txIndex];
        require(transaction.numConfirmatons >= numConfirmationsRequired, "cannot execute tx");
        require(transaction.daoApproval == true, "transaction not approved by DAO");

        transaction.executed = true;

        (bool success, ) = transaction.to.call{value: transaction.value}(transaction.data);
        require(success, "tx failed");
        transaction.daoApproval = false;

        emit ExecuteTransaction(msg.sender, _txIndex);
    }

    function transferTokens(address _to, uint _amount) internal {
        require(_amount <= address(this).balance, "amount execceds the available balance");
        tokenAddress.transfer(_to, _amount);
    }

I have a script to generate encodedFunctions:

const vault = await ethers.getContract("Vault")
const _amount = ethers.parseEther("10000");
  const encodedFunctionTransfer = vault.interface.encodeFunctionData(TRANSFER_TOKENS_FUNCTION, [GAURAV_ADDRESS, _amount]);
const encodedSubmitFunctionCall = vault.interface.encodeFunctionData(SUBMIT_TRANSACTION_FUNCTION, [SAGAR_ADDRESS, GAURAV_ADDRESS, SUBMIT_TRANSACTION_ID, WITHDRAW_AMOUNT,encodedFunctionTransfer]);

Here are the constants:

export const SAGAR_ADDRESS = "0x3124475af0ba367fFf33a5DC9BcE78c41f493713"
export const GAURAV_ADDRESS = "0x7032576BCF4a7fc07d083F3c6b1f320a75B17959"
export const SUBMIT_TRANSACTION_FUNCTION = "submitTransaction";
export const TRANSFER_TOKENS_FUNCTION = "transferTokens";
export const WITHDRAW_AMOUNT = 1000;

For one, that function is internal in your contract, so it is obviously not part of its interface.

How can I encodeFunction approveTransaction to pass function data from governor contract ?

function approveTransaction(uint _txIndex) public onlyGovernance()  notApproved(_txIndex) {
        isApproved[_txIndex][msg.sender] = true;
        emit ApprovedTransaction(msg.sender, _txIndex);
    }