Bistec is not the same as a Fajita.
Although Fajitas can be made with Bistec because Bistec is a Spanish Word that means Beef Steak.
Beef Steak also known as Bistec is used to make Fajitas with but they are not the same.
Bistec can also refer to a steak dish served with some onions and steak sauce on top.
So if you want to order Bistec you'll likely get a steak dinner with onions and steak sauce.
If you want to order a Fajita then you should order Fajitas.
Bistec is a Spanish dish that can be found in all former Spanish colonies, including the Caribbean islands of Cuba, Dominican Republic, and Puerto Rico.