To get started, use Phantom wallet to login to the website.
You should be able to directly connect with your Phantom wallet, provided it is setup completely, and access the website.
Since this project uses the Solana testnet, you do not need to spen real money/crypto to interact with it.
Once you authenticate using Phantom wallet, it should automagically change you to the testnet. In order to get testnet tokens, use the Official Solana Testnet Faucet to get a free airdrop of testnet tokens.