Morning Pages are three pages of longhand, stream of consciousness writing, done first thing in the morning. There is no wrong way to do Morning Pages–they are not high art. They are not even “writing.” They are about anything and everything that crosses your mind– and they are for your eyes only. Morning Pages provoke, clarify, comfort, cajole, prioritize and synchronize the day at hand. Do not over-think Morning Pages: just put three pages of anything on the page...and then do three more pages tomorrow.
https://juliacameronlive.com/basic-tools/morning-pages/
Joshwin Greene suggests writing for 25 minutes instead.
Chris Winfield says it needs to be longhand, because the slowness helps you. And also that you aren't "supposed to" read them afterward.