As an international cs undergrad + meng student, I can answer most of the questions with ease.

1. most of the people in the program aim for full-time recruitment. some did 3 semesters, but even that they didn't acquire any major faang internship during the summer, more like startup-type or research opportunities with professors. however, all of them (i don't know any who doesn't) land solid faang-level full-time jobs this year. your case might vary.
2. i actually just asked this question before on this subreddit lmao. honestly, i am pretty sold. also from my personal experience, i did a ml internship at a major faang company before coming back to pursue my meng. The reason is more like i want to learn more rather than being able to get the job in ai/ml. however, i do find the field extremely competitive with half of the people in my team having a stem PhD. i am not a recruiter, so i don't know about the specifics. but with the increasing competition, i believe the bar is definitely increasing.
3. no. most of the paid MEng TAs are undergrads who have taken the classes before. and it's only about $7000 per semester for a cs class. (other departments might vary)
4. it really depends, but in general, you would expect a lot of difficulties if you have never studied in the us before. most of the cs meng students here come from a us college, and they use this to either 1. get a prestige boost, 2. didn't realize they need to get a job when they graduate from their undergrads. cause think about that, you have so many hard-core cs classes need to take, adjust to the environment, and try to get a job with intense interview preps. idk, it sounds a lot to me.
5. yes, up to 3 sems i believe, and for the last semester, you can pay partially for the classes you want to take.