It's probably easier if you are outside of the USA to go through the bank/crypto membrane.
In the US, you really need to identify yourself to the exchange (like coinbase) for them to accept your bank traansfer.
I don't know if coinbase does business in Thailand. If not then there are probably other exchanges that do. I'm sorry, I'm not familiar with that part of the crypto-world.

As for transferring cryptocurrency to PayPal. He won't be able to do it. PayPal sees all types of cryptocurrency as a direct threat to their existence . They would do anything to they can to stifle its use.

Sorry I couldn't be more helpful. In many ways I am just learning myself.