Is he familiar with all the major civilizations/empires whether east or west or those in the middle ? How far back ?

It'll depend on a few things. I was a history major in undergrad. I transferred after my freshman year and, while the nuances differed, the overall major scheme was similar between the universities.

Generally, your university will require X overall history credits. Then you're going to have mandatory content requirements within the major. For example, I had to have a certain amount of credits from each region of the world, presumably to have some overall grasp of world history. I also had to have X amount of credits for certain time periods (e.g., at least one class that focused on the 17th century or something similar -- it has been a while so I don't remember the specifics.)

These weren't mutually exclusive for my degree and I expect they wouldn't be elsewhere. One of the classes I took to fulfill one part of each of these requirements was The History of British India, since it's a fairly focused time period (relatively speaking) and it covered South Asia.

There's typically a writing requirement. You're usually going to have to take 1-2 upper level writing courses that will involve a lot of independent research and writing a lengthy paper with rigorous citation. Obviously your work - including your cites - should always be thorough but the paper and smaller writing exercises are likely going to be held to stringent standards expected of a more practiced and focused academic.

Then I had my own concentration: the colonization of the new world and the formation/development of the early American republic. Basically, I took a lot of courses in this area, ranging from general survey courses to two writing courses.

I don't post much here because I'm so separated from the content that I defer to the folks who have made this their field, but I can recall information and themes well enough to have an intelligent conversation and tie it into overlapping topics (e.g., legal history.)

Bear in mind that being a history major isn't just about memorizing names, dates and locations. Your goal isn't to become an encyclopedia. You will look things up all the time. You're going to hone research and writing skills. You're going to think critically about the historical explanations presented to you. You're going to find ways to draw conclusions based upon your research. If you're a numbers person and can uncover the data, you might find yourself testing these hypotheses. You might end up crossing disciplines. You'll give presentations and have to learn to take complex or cumbersome material and break it down into easily digestible components for your target audience. This should really be the focus of your studies when majoring in history.

This really depends on the person's interests. My particular interest is 18-20th century Europe. Most of my classes where I have a choice are related to that. I also have to take some American and non western civilization classes. I have little interest in ancient times so the earliest period I've studied is the beginning of Islam about 700. Even my non western civ classes have been geared to Europe as I'm taking African history from 1750 (i.e. age of European colonialism). That said I could be looking into Rome or early China if I wanted. Before the dawn of civilization with Mesopotamia and Egypt and you are going to need to be a archeology major.