Chevron
A chevron is a V-shaped band on a flag. When the point of the V faces the fly it is called a hoist chevron. Flag writers sometimes use the word loosely for a solid triangle at the hoist, as on the flags of the Philippines and Czechia.
Strict flag dictionaries call that solid wedge a triangle and save chevron for the V-shaped band. Either way, the shape draws the eye toward the hoist and gives a natural place for a charge. The Philippines puts a sun and three stars in its triangle.
The flag maker has chevron and triangle-at-hoist layouts. Recolor the wedge and the stripes behind it, then add a star or a sun from the Symbols tab. The flag design ideas guide covers this layout family, and you can make your own flag from either one.