No it is not the same. When a beef is butchered it is hung on a rail in two pieces or halves. Then each half is cut in half so the carcass is in quarters now. You have a forequarter and a hindquarter. The flank steak comes from the hindquarter and the flat iron steak comes from the forequarter.
Beef - it is a cross-cut shank
The hindquarter or rump, just like in any other breed of cattle.
Silverside Beef.
"Sirloin" is he cut of the beef from near the rump.
Beef that is cut into strips and dried / cured is often referred to as beef jerky.
Cut the beef into many and cook it with the noodles
This is the heart of any cut of beef against the grain. If it was a pave of rump, it would be the middle / best / heart of the meat / rump, cut against the grain.
If there is a label on the carcass that entails that it is an Angus beef product, and if there is a CAB (Certified Angus Beef) label on the package, then that tells you that the cut of beef is Angus. Without such labeling, you really wouldn't know what breed of bovine the cut of beef came from.
tail end or backside
Beef tenderloin is a cut of beef taken from the loin area, it is usually a roast.
It depends on the thickness of the beef, and the cut of beef.