Although there really is no rule about what kind of underwear to wear, there are more “appropriate” undergarments you should use depending on the clothes you wear.
For example, if the fabric of your outfit is very light and stretchy, or if you are wearing something tight, you might want to wear a thing or g-string so that your panty line won’t be visible.
Bikini cuts are comfortable to wear and they cover the buttocks fully. They can easily be hidden under a pair of jeans with a reasonable rise. Bikini cuts also have less tendency to ride up.
During winter, or when you are wearing clothes with thick fabrics, you may opt to wear boy shorts.
Shapers would work if you are wearing a form fitting dress and you would want to hide bulges. There are different cuts to shapers depending on the dress or clothes you will wear.