I'm looking forward to being treated by you next time at a café.
I can't wait to be treated by you at a café next time.
ご質問ありがとうございます。
① "I'm looking forward to being treated by you next time at a café."=「次回、あなたにカフェでおごってもらうのを楽しみにしている。」
② "I can't wait to be treated by you at a café next time."=「次回、あなたにカフェでおごってもらうのが待ち遠しい。」
ご参考に。