There are over 100 M.Arch programs in the US and each has its own requirements.  Many require the GRE, but not all do.  Similarly, some offer some scholarships for which international students may be eligible, and some do not.  You'd need to narrow down your list of schools and then look into their individual programs. 

At the moment there is high demand for architects in the US.  But the field is cyclical, there have been major ups and downs roughly every 8 to 10 years over the last few decades, and during the last recession unemployment in the field was as high as 40% in some regions of the US.  Most universities report higher numbers of applicants to professional degree programs during economic downturns, so your chances of admission and better financial assistance may be higher now during a building boom - but the downside of that is that if you enter an M.Arch program now then you may very well be entering the field as a fresh grad during the next downturn. 

If you're so on the fence that you don't even know if you really want to study architecture, or planning, or graphic design... well it's going to be difficult to narrow down a list of M.Arch programs.  By the time you get to considering grad programs it's generally expected that you not only know that you definitely want to study architecture, but you have some idea of your interests within architecture, which will help you target a program.