Is it currently possible to come in and get a tourist visa on landing in Thailand ? And then extend the visa here in Thailand when it expires - my son needs to come here for about 4 months. Flying in from France. Australian/ British passports.
TLDR : Answer Summary
Currently, you cannot get a tourist visa on landing in Thailand. Instead, you should obtain a tourist visa from a Thai consulate before traveling. However, as an alternative, your son can enter Thailand visa-exempt if he holds an Australian or British passport, which allows for a 45-day stay without a visa. If he needs to stay for about four months, he can extend his stay while in Thailand.