For you to understand it easier, take this logic.
Litecoin = plain as cash
Chainlink = just like Ethereum that can built another project. It has a smart contract for which other projects were made of.
Yeah pretty much this one, Litecoin is a small brother to Bitcoin, so definitely functions the same. So it's been used for many real life usage, like gambling for example. You can used Litecoin to deposit to some gambling platform. Chainlink is a would be competitor of Ethereum, "decentralised" network for smart contract used.