Oh, I can agree that Moscow is an amazing city to visit, and you won't be disappointed. Have you already got a visa? It's a really important step, so I highly recommend you to 
get russian visa online. I used it when I was planning my trip to Russia, and it helped me a lot. Also, try eating at the cafeterias instead of fast-food restaurants because it's cheaper and healthier, and there are many cafeterias in Moscow.