Yes, you can find the latest Blocknumber in a series of API suppliers.

• https://toncenter.com/api/v2/#/blocks
• https://sandbox-v4.tonhubapi.com (Test-net)

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 });