I'm trying to deploy a smart contract to an Ethereum testnet (e.g., Rinkeby) via Remix Desktop. I have an RPC url provided by Infura, and I'm using this RPC url for Web3 Provider. Remix Environment does switch to Rinkeby successfully; however, I'm not able to add a new account. It asks for a passphrase, and when I enter some arbitrary passphrase, it gives me an error: "Cannot create an account: Error: Returned error: The method personal_newAccount does not exist/is not available"

Am I doing something wrong here? Your help would be greatly appreciated!