When you stay in any foreign country, learning the language is usually a good idea. The ability to understand and communicate, even if only a little, will make your life so much more interesting and fun. This is especially true here in Japan and I do recommend that you take time in your busy schedule to at least give it a try.
Japanese, with its different writing systems, especially the Chinese characters (kanji) may at first seem just too hard but if you try to do a little every day rather than taking on big chunks at once, it is possible. Try to memorize 3-5 kanji everyday. After 3 months, you will be able to recognize kanji everywhere. On the train, in the shops, etc. You might be surprised at how much you will enjoy it.
There are many Japanese language schools where you can find good teachers, but don’t forget the many volunteer groups that have so much to offer. Their teachers may not always be licensed to teach Japanese but they will have all the information about that city/area and will be a great source to you to learn not only the language but all the cultural events, festivals, and other fun things that happens in your neighborhood.
You can find information about such groups at your local city office and prefecture office.
Below, I have included some WebPages that might be useful.