Yes. Your brand and your website are the same thing on Forxample, one doesn't exist without the other. When you delete your brand, everything goes with it: your website, your content, your posts, your customer data, and all your settings. There's no way to recover any of it once it's done.
If you're not ready to lose everything, cancelling your subscription is the safer route. Your brand stays intact and nothing gets deleted, you simply won't be charged going forward.

