To embed a Twitter post simply add the URL of the Twitter post on a line by itself. You can find the URL by clicking on the date of any twitter post. For example:
https://twitter.com/elonmusk/status/1623014136258117633
becomes
Going forward, Twitter will be broadly accepting of different values, rather than trying to impose its own specific values on the world
— Elon Musk (@elonmusk) February 7, 2023