OK thanks everyone. I’ve made some progress with your help.
My main issue with the 787 engines cutting off was because I didn’t pay enough attention to the fuel control just aft of the throttles, as was mentioned above. Once I flipped those on the engines remained on after starting. I was even able to make my first 787 flight and visual landing.
I did have other troubles, such as not being able to start the engines without Cntrl-E, the plane not following the flight plan, and some of the AP buttons not being able to be turned off in flight. But I will try to spend the time to learn.