TM30. Very short for the registration of a foreigner arriving at an address in Thailand within 24 hours.
The registration is free, but need to done in 24 hours after arriving, if to late there are fines.
The owner might willing to register and report you using this on line system, if not the owner has to supply you with documents to register in person at Immigration Office.
BTW strange to read you find a school that is willing to support you with an ED visa as all schools are closed by Government orders.
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