Start by doing some heavy reading - Insight Guides and Lonely Planet have extensive libraries of travel books. Spend a lot of time online as well. The scope of your questions says, and I could be wrong, but don't think so, that you haven't done much research, which is a big mistake. You need to make a budget based on actual costs, not guesswork or random answers from strangers on the web.

FYI, some of the countries on your list are some of the most dangerous places on the planet for Western travelers. If you've never done any traveling before, and I doubt you have, based on your questions about visas and other basic considerations, I suggest scaling back your trip and going to some friendlier places.