Ash here from the Shopify team. Welcome to the Shopify Community!
Our online Help Center has step by step instructions on how to close a Shopify store. Once a store is successfully closed, the subscription is cancelled and no further billing will take place. We guarantee to keep the information on file for 30 days in case the owner wishes to re-activate the account, but after those 30 days the information is subject to removal from the platform. If you think there's any data that you want to retain after closing the store, check out our documentation on making backups and duplicates of content from your store.
Before you proceed with closing the store, may I ask if there's a specific reason behind this decision? If you're experiencing any roadblocks to success, I'm happy to discuss some strategies and offer my assistance. Additionally, we have a couple options for pausing your store. You're able to pause your store and continue to work on it for a reduced rate, or pause it completely and step away from it for a limited time.
Let me know if I can help out in any way before making a final decision.