Fetching all nfts belonging to a collection

Hey, I am new to web3 and solana, and I wanted to know if there is any way to fetch all nfts from a collection? How do we identify a solana collection? There is no smart contract address like we have in etherium i guess. So how do we fetch nfts of that collection. Does the collection have any public keys or something? Sorry if I am saying meaningless things, I am real new to this field.