Once you have a suitable Visa approved , Yes once you get here - if you have a Non-O or one of the retirement visas ( over 50 ) - a Thai bank account is one of the first things you need to turn your - Non-O Visa ( 90 days ) into a 12 month extension.
If you are keen to try on your own go to one of the banks , ask their for requirements and see how you go . After reading many posts everyday , It appears to be not that easy , You may need to use a Visa agent to help .
But Yes 100% you need a Thai bank acc . To fulfill the requirements of a 12 mth extension