How to create an account on NEAR protocol?

I would like to learn how to create an account using RPC or REST calls on NEAR protocol.

If you want to create a subaccount (a.frol.near when you own frol.near): Submit a transaction with CREATE_ACCOUNT, TRANSFER, ADD_KEY actions. Here is an example of such a transaction.

If you want to create *.near account, you need to submit a transaction with create_account function call on near contract. Here is an example of such a transaction, and here is a code snippet from the tutorial in the docs using near-api-js JS library:

const HELP = `Please run this script in the following format:
    node create-testnet-account.js CREATOR_ACCOUNT.testnet NEW_ACCOUNT.testnet AMOUNT
`;

const { connect, KeyPair, keyStores, utils } = require("near-api-js");
const path = require("path");
const homedir = require("os").homedir();

const CREDENTIALS_DIR = ".near-credentials";
const credentialsPath = path.join(homedir, CREDENTIALS_DIR);
const keyStore = new keyStores.UnencryptedFileSystemKeyStore(credentialsPath);

const config = {
  keyStore,
  networkId: "testnet",
  nodeUrl: "https://rpc.testnet.near.org",
};

if (process.argv.length !== 5) {
  console.info(HELP);
  process.exit(1);
}

createAccount(process.argv[2], process.argv[3], process.argv[4]);

async function createAccount(creatorAccountId, newAccountId, amount) {
  const near = await connect({ ...config, keyStore });
  const creatorAccount = await near.account(creatorAccountId);
  const keyPair = KeyPair.fromRandom("ed25519");
  const publicKey = keyPair.publicKey.toString();
  await keyStore.setKey(config.networkId, newAccountId, keyPair);

  return await creatorAccount.functionCall({
    contractId: "testnet",
    methodName: "create_account",
    args: {
      new_account_id: newAccountId,
      new_public_key: publicKey,
    },
    gas: "300000000000000",
    attachedDeposit: utils.format.parseNearAmount(amount),
  });
}

If you don't need a named account, you can just generate a new ed25519 key-pair, and the hex representation of the public key will be your account id (it won't be recorded on chain until you/someone transfers some NEAR tokens to it, and so it is called "implicit" account). Example for such an account.

Here is a detailed tutorial on how to construct a transaction. Ultimately, you will submit your transaction via JSON RPC broadcast_tx* endpoints.