Yash, you cannot just pick up and move to Japan and become a permanent resident or citizen. You are pretty young, so lots of time to think about this yet, but when you first come to Japan you will need to come as a student or have a job already arranged (for this work visa you need to have graduated university).Once you have been in Japan for a number of years on one of these visas (10 years, or shorter if you are married to a Japanese citizen) you can apply for permanent residence. Some years after that, you can apply to be a citizen.
If you have a Japanese parent then you may be entitled to residence or citizenship- is this the case for you?
In any case, we have written a lot about this topic on this site, so look at the A-Zs and Living in Japan section for previous discussions on this topic.
