You will need a non-custodial wallet to be able to purchase an NFT. OpenSea accepts wallet payments from <a href="https://metamask.io" rel="noopener" target="_blank"><u>MetaMask</u></a>, <a href="https://www.portis.io" rel="noopener" target="_blank"><u>Portis</u></a>, and <a href="https://registry.walletconnect.org/wallets" rel="noopener" target="_blank"><u>WalletConnect</u></a> compatible wallets for secondary market sales. You will need to transfer ETH into one of these non-custodial wallets.