if you want to go the 65k transferred into Thailand for 12 consecutive months for retirement your first year MUST BE 800k in your Thai bank account not dropping below that for 3 months after your first extension stamp and CANNOT drop below 400k for the rest of the year.
you don’t. When ENTERING Thailand by land borders you fill in the TM6. TM30 is for notification of address to the immigration in the province you are staying