You cannot go restaurants every day or want to save your travel budget so that you may want to find a deli section at supermarkets or deli stores. I think, in our culture, this section or industry is well developed rather than frozen meals compared to the US. Some are reasonable prices. Like other countries, they may offer special prices for different products every week, and discount prices several hours before they close the stores, expecially in the deli and fresh fish or meet sections. During your travel, because you may not have a choice of cooking, deli sections or stores may help your travel budget as well as give you a great chance to taste real traditional Japanese meals. To you, it will be a great adventure.
So what the "deli section" is called in Japan? It is usually called "お惣菜コーナー（おそうざい こーなー）Osozai kohnah". "惣菜：souzai" generally indicates fully- or pre-cooked side dish which is particularly sold at stores. In the "お惣菜コーナー: osozai kohnah" there may not only be "惣菜：souzai" but also sushi, bento-box, and other variety of cooked meals. Here is some items of cooked food usually in the "お惣菜コーナー： osocai kohnah". (Click the Japanese below so that you'll see the image of these.)
寿司: sushi (usually pricy but I am sure that it may be cheaper than in some other countries.)
コロッケ： Korokke (fried mashed potato or other vegerable covered with Panko-bread craft, usually there are several different tastes)
(お)弁当：(O)bentou: looks like a meal combo. It usually consists of steamed rice w/, w/o a pickled plam (red one) or black sesami seasoning and cooked meat or fish, and vegetable.)
焼き鮭 弁当：Yaki-zake or sake bentou, it is acceptable if it may not be hot.
焼き肉 弁当： yakiniku bento, Find out a microwave at the store.
豚 生姜焼き 弁当: buta-shouga-yaki bentou, (buta-shouga yaki: pork saute based on soy-sauce spiced with ginger.)
鶏 唐（揚げ） 弁当: Tori-cara(age) bentou, the bento just after cooked is always the best.
海苔 弁（当）: Nori ben（tou）. (soy-sauce tasted seaweed sheets on steamed rice) Usually very cheap but sometimes greasy by fried side-dish.)
These are very popular items at the grocery stores or supermarkets. In the next discussion, we will learn how to ask where the "お惣菜コーナー：Osozai Kohnah" is in Japanese.
Learn from sounds
弁当の日の歌 （べんとう の ひ の うた: Bentou no hi no uta）
This is also some review included in this song. Can you catch some words in this song?
Bentou no hi (弁当の日）
itadaki masu （いただきます）
gochisou sama （ごちそうさま）
Korokke （コロッケ）*See below.
Additonal expression in this song
Oishii(ne) おいしい（ね）: delicious, "-ne" will be used when expressing the impression or your expectation of agreement like "It is delicious, isn't it?"
Kansha (感謝): Thankfulness
Shiawase （幸せ）: happiness