Gakushikaikan is locating in Chiyoda-ku, it’s right next to to Jimbocho Station. They have 4 restaurants: Nishiki (Japanese dishes), Latin (French dishes) - this is a course menu - I quite recommend this, Koromu (Chinese dishes), Seven’s house ( pub)
If you like sushi, try it at Tsukiji market. Curry shops around Jimbocho station.In the summer, I recommend you try zaru-udon or zaru-soba, kind of cold noodles, better to eat with Tempuras. I usually eat at Marukame Udon restaurants. The others are Gyudon, Oyakodon, Motsuni, Miso Ramen or Soy R...
For 1 person in the center is about 80,000¥~12,0000¥. In Tokyo but not at the center will take at least 50,000¥.Or you can find apartments around Chiba or Saitama, it’s not only close to Tokyo but also from 50,000¥ you could find a better room than in Tokyo.