@Henf ****
Starting a business is totally possible but it usually requires a lot of money from your pockets for visa, permits, lawyers, and then you will need to think of what kind of business you are wanting to start. I must admit that learning Thai has helped me in a lot of situations but at the end of the day you should think of what's better for you. One piece of advice I can offer is. One of the most important things when it comes to business or legal paperwork in Thailand is, who you know. Cheers