Sergeant Major of the Army is the highest rank NCO.
Yes, and I was one of them
In the US Army, there's two ranks - Specialist, and Corporal. In the US Marines, it's just Corporal. The Specialist rank in the Army is not an NCO rank, whereas Corporal is.
In the US Army, General.
The highest Non-Commissioned Officer rank in the US Army is Sergeant Major of the Army. The current SMOA is Kenneth O. Preston.
Which Navy did you have in mind? There is no such rank in the US Navy. Command Sergeant Major is a high enlisted rank in the US Army, and denotes the senior NCO of whatever unit or element they hold the position in (it can be anywhere from Battalion to Army level).
Presuming you mean "chief", the highest ranking officer in the British army is called a Brigadier.
Chief of Staff is the title of the highest ranking officer of the US Army. He holds the rank of General, which is an 0-10 / 4 star rank. The title of Commander-In-Chief is given to the President of the US and is the commanding authority for all military forces, but the holder of this rank, while often having served in the military, is not a military officer by virtue of title.
T5 was a rank in the US Army and Army Air Force in WW II is stood for Tech 5, it was equal to a corporal in pay but lacked the command of a corporal. The rank on the uniform was a corporal stripes with a "T" under them. He was the most junior of the NCO ratings.
General of the Army (five stars). However, this is a special rank used only in wartime. Currently, General (four stars) is the highest achievable rank.
Command Sergeant Major is the highest enlisted rank in the US Army
A person that is chief of a army group ( The leader ).
The Chevron to a US Army NCO is used to indicate first sergeant is a mark of distinction and was used in heraldry to indicate achievement.