Can email verification be sent only when a user registers for a specific membership?

I am using MemberPress for user management and membership handling on my site. Since MemberPress does not provide account or email verification, I am using a third-party user verification plugin to handle this process.

Currently, I have a free membership level that users register for, which grants access to free courses. After registering, they can subscribe to a paid membership to access more features. My question is: how can I ensure that the email verification is sent only when users initially register for the free membership level, and not when they upgrade to a paid membership later on? I want the email verification to happen only once, during the free membership registration.

Thanks!