OK. So you're Burmese. To be honest, I think you'd have better answers if you asked on a Burmese group for migrant workers as I'm pretty sure you have more options than than what is usually discussed here. To answer your question: 90 day visa usually mean some sort of non immigrant visa tgat allows to stay with family, volunteering or business. Some other countries (I forget wich ones) can get a 90 day tourist visa. I don't think Burma is one of them.
You can enter on 45 days (extendable by 30 days) or, as mentioned, get the 60 days (also extendable for 30 days) gives you a bit more time. And you can then purchase a 90 day visa (non o based on retirement) wich you can then extend for 1 year