We need information, please.

I am 21 years old. I only have a high school education, with a little college as well and wish to try something new, and exciting. While speaking with a friend of mine, he suggested we try moving to Japan. The important thing I need to know: Is such a thing possible? I have been taking Japanese language classes since I was 18, and enjoy it very much. I have also been saving a lot of money so the myself and my friend may go and do this. Can someone please help me with any information I may need to do this? I'm worried something may go wrong if I do not know all the current details.
Thank you very much.

Move to Japan to do ....?

Again use the search function. Depending on what country your nationality is, you might qualify for a working-holiday visa, but if you don't come from a country with a working holiday visa then to work you'll need a work visa, and looking at your situation to get a working visa you need a bachelors degree.

Where are you from? If you are from Canada, UK, Australia or New Zealand you are eligible for a working holiday visa and will be able to stay in Japan for one year, during which time you can look for work- possibly in the hospitality industry or teaching English. This visa is not available to Americans.

If you have the funds you can look at getting a student or cultural visa and coming here to learn Japanese, martial arts or a traditional skill.

Without a Bachelor's degree you are not eligible for a full working visa unfortunately.

Have a look at the Japanese MOFA (Ministry of Foreign Affairs) website for more info on visa eligibility.