Yes, you can find the latest Blocknumber in a series of API suppliers.
Or using the follow of code from orbs network
// copy paste the following snippet into your dapp client code
// to initialize your favorite TON API library and make blockchain queries
import { getHttpEndpoint } from "@orbs-network/ton-access";
import { TonClient } from "ton";
// get the decentralized RPC endpoint
const endpoint = await getHttpEndpoint();
// initialize ton library
const client = new TonClient({ endpoint });