Good luck getting citizenship...It is an extremely long and difficult process. To start you have to have a Non-Immigrant visa and be in thailand on 3 yearly extensions. In addition, you will need a work permit and to pay taxes to gain permanent resident status. Then you need another 5 years as a permanent resident to qualify for citizenship. As well as be able to speak and read Thai. Very very few people are able to do this as the process is complex, long and difficult.