Start

https://github.com/dappuniversity/web3_examples

https://sotoedu.herokuapp.com/

getBalance

let getbalance = await web3.eth.getBalance(fromaddress);
let balance = web3.utils.fromWei(getbalance, "ether")

if (DEBUG) console.log("balance : ", balance + " ETH");
$('#message').text(" balance: " + balance + " ETH");

send transaction

const privateKey = Buffer.from(myPrivateKey, 'hex');
if (DEBUG) console.log("privateKey: ", privateKey);

web3.eth.getTransactionCount(fromaddress, (err, txCount) => {
// Build the transaction
const txObject = {
nonce: web3.utils.toHex(txCount),
to: toaddress,
value: web3.utils.toHex(web3.utils.toWei(amount, 'ether')),
gasLimit: web3.utils.toHex(21000),
gasPrice: web3.utils.toHex(web3.utils.toWei('10', 'gwei'))
 }

 // Sign the transaction
 const tx = new ethereumjs.Tx(txObject);
 tx.sign(privateKey);

 const serializedTx = tx.serialize()
 const raw = '0x' + serializedTx.toString('hex')

 // Broadcast the transaction
 web3.eth.sendSignedTransaction(raw, (err, txHash) => {
console.log('txHash:', txHash)
  // Now go check etherscan to see the transaction!
  })
})  // end of txbuilder