update buy subscription details (#18977)

content/billing/build-billing.md

@@ -10,13 +10,15 @@ In this section, learn how to set up and manage billing for your Build Cloud sub
 
 ## Buy your subscription
 
+You can buy a Build Cloud subscription on a monthly or annual plan.
+
 1. Go to the [Docker Build Cloud dashboard](https://build.docker.com/). If you're not already signed in to your Docker account, do so now.
 2. Choose the user account you want to use to subscribe. This can be a personal account, or an organization account. To buy a subscription for an organization, you need to be an organization owner.
 3. Review the plans, then select **Buy now**.
 4. For organizations: Select the number of seats you want to buy, then select **Continue to payment**.
 5. Review your order, then enter your payment information and select **Subscribe**.
 
-Subscriptions charge monthly to the default payment method.
+Subscription renewals charge to the default payment method.
 
 ## View billing history and manage your billing information