Set RPC
Create a connection to an RPC
New Way
import { createSolanaRpc } from "@solana/web3.js";
const rpc = createSolanaRpc("https://api.devnet.solana.com");
Old Way
import { clusterApiUrl, Connection } from "@solana/web3.js";
const connection = new Connection(clusterApiUrl("mainnet-beta"), "confirmed");
You can find RPC providers here (https://solana.com/rpc)[https://solana.com/rpc]