Arbitrum, an Ethereum layer-2 network, facilitates the development and deployment of scalable smart contracts at a reduced cost, leveraging Chainlink Data Feeds to integrate off-chain data, such as reliable asset prices, for DeFi applications. This article provides a comprehensive guide on using Arbitrum, starting from setting up on the Arbitrum Rinkeby Testnet to deploying smart contracts with Chainlink Price Feeds, which offer crucial external data to ensure security against price manipulation attacks. It highlights the importance of accurate data from Chainlink oracles in creating robust DeFi applications and introduces the concept of Optimistic rollups, a key component of Arbitrum that enhances transaction speed and cost-efficiency. The tutorial also outlines the use of the Chainlink L2 Sequencer Health Flag to ensure the reliability of transaction sequencing, thereby maintaining operational continuity during sequencer downtimes. Overall, the knowledge shared empowers developers to harness Arbitrum's capabilities and Chainlink's data precision to build advanced, secure smart contracts.