The converttopsbt RPC converts an unsigned raw transaction to PSBT format. It ignores existing signatures.
converttopsbt "hexstring" ( permitsigdata iswitness )
*bitcoin-cli help converttopsbt
converttopsbt "hexstring" ( permitsigdata iswitness ) Converts a network serialized transaction to a PSBT. This should be used only with createrawtransaction and fundrawtransaction createpsbt and walletcreatefundedpsbt should be used for new applications. Arguments: 1. "hexstring" (string, required) The hex string of a raw transaction 2. permitsigdata (boolean, optional, default=false) If true, any signatures in the input will be discarded and conversion. will continue. If false, RPC will fail if any signatures are present. 3. iswitness (boolean, optional) Whether the transaction hex is a serialized witness transaction. If iswitness is not present, heuristic tests will be used in decoding. If true, only witness deserializaion will be tried. If false, only non-witness deserialization wil be tried. Only has an effect if permitsigdata is true. Result: "psbt" (string) The resulting raw transaction (base64-encoded string) Examples: Create a transaction > bitcoin-cli createrawtransaction "[{\"txid\":\"myid\",\"vout\":0}]" "[{\"data\":\"00010203\"}]" Convert the transaction to a PSBT > bitcoin-cli converttopsbt "rawtransaction"