getStakedAmount.js

const ethEnabled = async () => {
  if (window.ethereum) {
    window.web3 = new Web3(window.ethereum);
    return true;
  }
  return false;
};

async function getStakedBalance(accountId) {
  await ethEnabled();

  var contractAddress = '0x5c8D727b265DBAfaba67E050f2f739cAeEB4A6F9';
  var abi = JSON.parse('[{"inputs":[{"internalType":"contract BananaToken","name":"_banana","type":"address"},{"internalType":"contract BananaSplitBar","name":"_bananaSplit","type":"address"},{"internalType":"address","name":"_devaddr","type":"address"},{"internalType":"uint256","name":"_bananaPerBlock","type":"uint256"},{"internalType":"uint256","name":"_startBlock","type":"uint256"},{"internalType":"uint256","name":"_multiplier","type":"uint256"}],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":true,"internalType":"uint256","name":"pid","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"amount","type":"uint256"}],"name":"Deposit","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":true,"internalType":"uint256","name":"pid","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"amount","type":"uint256"}],"name":"EmergencyWithdraw","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":true,"internalType":"uint256","name":"pid","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"amount","type":"uint256"}],"name":"Withdraw","type":"event"},{"inputs":[],"name":"BONUS_MULTIPLIER","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_allocPoint","type":"uint256"},{"internalType":"contract IBEP20","name":"_lpToken","type":"address"},{"internalType":"bool","name":"_withUpdate","type":"bool"}],"name":"add","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"cake","outputs":[{"internalType":"contract BananaToken","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"cakePerBlock","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"contract IBEP20","name":"_lpToken","type":"address"}],"name":"checkPoolDuplicate","outputs":[],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"},{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"deposit","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_devaddr","type":"address"}],"name":"dev","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"devaddr","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"}],"name":"emergencyWithdraw","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"enterStaking","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_from","type":"uint256"},{"internalType":"uint256","name":"_to","type":"uint256"}],"name":"getMultiplier","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"}],"name":"getPoolInfo","outputs":[{"internalType":"address","name":"lpToken","type":"address"},{"internalType":"uint256","name":"allocPoint","type":"uint256"},{"internalType":"uint256","name":"lastRewardBlock","type":"uint256"},{"internalType":"uint256","name":"accCakePerShare","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"leaveStaking","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"massUpdatePools","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"},{"internalType":"address","name":"_user","type":"address"}],"name":"pendingCake","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"}],"name":"poolInfo","outputs":[{"internalType":"contract IBEP20","name":"lpToken","type":"address"},{"internalType":"uint256","name":"allocPoint","type":"uint256"},{"internalType":"uint256","name":"lastRewardBlock","type":"uint256"},{"internalType":"uint256","name":"accCakePerShare","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"poolLength","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"},{"internalType":"uint256","name":"_allocPoint","type":"uint256"},{"internalType":"bool","name":"_withUpdate","type":"bool"}],"name":"set","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"startBlock","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"syrup","outputs":[{"internalType":"contract BananaSplitBar","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalAllocPoint","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"multiplierNumber","type":"uint256"}],"name":"updateMultiplier","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"}],"name":"updatePool","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"},{"internalType":"address","name":"","type":"address"}],"name":"userInfo","outputs":[{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"rewardDebt","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_pid","type":"uint256"},{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"}]');

  var contract = new web3.eth.Contract(abi, contractAddress);
  var pidOfFarms = 78;

  var stakedAmount = 0;
  var getUserInfoPromise = contract.methods.userInfo(pidOfFarms, accountId).call().then(result => {
    return web3.utils.fromWei(result[0], 'ether');
  });
  var getAmountPromise = getUserInfoPromise.then(amount =>  {
    stakedAmount = amount;
  });

  await getAmountPromise;

  return stakedAmount;
}