I'll leave a note so that anyone you talk to will be able to help you.
I'll make sure someone will be able to assist you when you call.
①I'll leave a note so that anyone you talk to will be able to help you.
「(話を受けた人が)誰でもヘルプできるようにメモしておきます。」
I'll leave a note→メモしておく
be able to help you→あなたのお役に立てる
②I'll make sure someone will be able to assist you when you call.
「お電話を頂く際に、必ず誰かがサポートできるようにしておきます。」
I'll make sure→必ず○○しておく
be able to assist you→貴方のお役に立てる
少しでもご参考になれば幸いです。