Google onward flight or ticket. Last time I got one it was £14 when you arrive in Thailand put it in the bin. It's legit you will only need it if airline asks,and it's always there if imagration ask.
Iv had k bank account for many years, have a standing order from my uk account. When I come back to uk now and again I send international bank transfer. Never used wise or any other company like that ,never had any problems, it's when the thai banks don't know where money comes from that's the problem.
I know so .Iv been living here about 14 years married with 2 daughter's. I have to go back to uk now and again, I send money from my account in UK to my green bank in Thailand never no problem but £25 charge ever time I send