Hi @Sam_Son_쌤_샘, welcome to the Asana Community Forum and thanks for sharing your feedback with us!
As it stands, it’s currently not possible to see all recurring tasks in Workload, the new task will be created when the recurring task is marked complete. We already have a thread on this topic, I suggest you to upvote for this feature here: Visibility of all Recurring tasks
As a workaround, you could also set a date range for the entire week for the main task and assign subtasks for each day to your client so they can mark it complete every day. The hours of the subtasks won’t count as they are not associated with the project so you can set the exact effort in the main task for the week.
Your solution is also great! 
I hope this helps! I’m moving your thread to our usecases category so other forum members can share their tips with us as well!