You probably want to create a wallet for Bitcoin. This allows you to receive and spend bitcoin. There are many to choose from, so do your research before you settle on one.
For a beginner, I feel that Electrum is really one of the best to start with. It's a very light client so you don't need to download the entire blockchain and it gives you a lot of flexibility and control over how you decide to use your coins.
Whatever it is, just make sure the wallet you choose gives only you full control of your private keys, doesn't know it and doesn't store it. In short, avoid any online-based wallet where you typically access your "account" with a username and password. These wallets are controlled by a third party, not by you.
Note: Whenever you install your wallet you'll be given a set of words, write them down safely where they will never get lost and never show anybody.
If you lose those words then your bitcoin/Litecoin will be lost forever.
The set of words Xynerise given to you is usually called the "recovery phrase" or "recovery seed", if you somehow lost them but you still have access to your wallet, you can usually still retrieve the seed/phrase from inside the wallet. As it suggests, it lets you recover your wallet and funds if something ever happens (your device crashes, or your wallet files get corrupted, for example).