Dorico SE for Mac

Help me,

Dorico ask me a licence, but Dorico SE doesn’t is it free?

Yes, it is free, but in order to receive the free license, you need to register with Steinberg.
Go to the page Dorico SE: Free Music Notation Software | Steinberg and click on the field DOWNLOAD FOR FREE.
That leads you to a page where you can create a Steinberg ID. If you register with your e-mail address, an activation code will get automatically sent to you.