Doorways offer no extra protection unless the building was built before something like 1920.
If you go outside of a building during an earthquake, please get 150% of the height of the building between you and the building (and all other buildings) so you don’t get creamed by falling debris.
The “triangle of life” (never heard that one before) was recommended during a Community Emergency Response Team training session by senior firefighter IF, and only if, you’re in a big box store like Home Depot. If an earthquake hits during one of those, climb in one of the shelves if you can. Failing that, get all the way up against an external wall, because if the ceiling collapses, it’s unlikely to come down straight down the wall.