フローでのLeadの変換について、まずは関連情報を整理したいと思います。
質問的には、特別感はないです。ただコーディングを最初から排除している私が一番嫌いな質問。
まず、how can i do with the help of Flows without writning a code. とか書かれていたら
分かっていても答えません。経験的にこういう人って回答しても逆切れするか、質問ごと消して再投稿する。
まぁ、そこはどうでもいい。今回の回答が重要です。さすがお師匠さんの回答。
Auto Convert Lead without Code, with the help of Flows
Flows do not have an action to convert a lead - you must build one yourself, which you can't do on professional edition. Your only option is to find an ISV application with an invocable method to convert a lead included in the package, but a quick search doesn't show anything of that sort.
Of course, you can always try to convert the lead manually as part of the flow. The flow can receive a lead ID, and use the information from the lead to create an account and a contact, but it wouldn't work like normal conversion.