I've moved this thread to MV Support. Please be sure to post your threads in the correct forum next time. Thank you.
Tutorials is for Tutorials you have written for others to read, not to ask questions.
There is an event command "change party member", that is what you need to use in the event.
If you have too much trouble with the basics, I suggest you follow the link "starting point" in my signature and work through those tutorials, that will get you the basics as fast as possible.