You need to have minted NFTs of the desired format and own these NFTs, plus some amount of native tokens of the chosen network. If you don’t know where to start with NFTs, feel free to contact us for some help
The dashboard has an option for the link creator to “sponsor” the claim transaction, this will allow users to claim NFTs without paying for gas (it will be secured in advance and sourced from the contract at transaction). It costs 0.3 MATIC or 0.02 ETH depending on chosen network. The unused amount could be refunded using dashboard after the campaign ends.