We have just added a lot more blocks to use in the Block Editor.

Unfortunately the Forms are not working properly. The Developers are working on a fix.

Workaround

In the meantime the Jetpack Contact form still word as expected in the classic editor. If you switch to the classic editor for a post or page you can create a form there.  Contact forms can be used for gathering information of all sorts, not just contacts. More information on the Jetpack Contact form in Glow Blogs.