Where are you located in Thailand / where do you want to rent one?
You say, you have experience riding two-wheelers, but do you have the appropriate driving license to ride a Scooter? Please Note driving License AM (Europe) only is valid (AFAIK) for 50cc scooters, and the ones in Thailand are bigger CC ones (100cc for example) and that requires an A (A1,A2 or A) license.
Ps: Without a valid license and you get into a crash your travel insurance will NOT pay.
https://en.wikipedia.org/wiki/European_driving_licence#Categories_valid_in_all_EEA_member_states