Microsoft Forms is available in Preview in the following Office 365 commercial suites: Office 365 Business Essentials, Office 365 Business Premium, and Office 365 Enterprise E1, E3, and E5 plans. Microsoft Forms is also available to existing Office 365 Enterprise E4 customers who purchased E4 before its retirement."

 

Read more here - https://support.office.com/en-us/article/Frequently-asked-questions-about-Microsoft-Forms-495c4242-6...