To extend on retirement you need a minimum of 800k baht in a Thai bank account for at least 2 months before you apply or a minimum of 65k baht each month transferred in for the previous 12 months
She still has to go to Bangkok for biometrics at VFS global even with an agent. Agents still have to fill the same application form in.It’s not difficult to do yourself
If you want a Muay Thai. Education visa you will be expected to attend the course full time and extend the visa every 3 months at immigration subject to a satisfactory report from the school to immigration. They will check don’t think they won’t