You can ’embed’ an O365 form in a blog by pasting the url into a post on a line by itself. Eg: https://forms.office.com/Pages/ResponsePage.aspx?id=oyzTzM4Wj0KVQTctawUZKSmIYBesqWVJqR5zz1mWNAVUOU1CUzVWOVFRUjc5RFcxQlJPTlhXMFVUNS4u

It will embed like this:

Not a true embed but a link to the form.