If you travel around Thailand as a backpacker even just for a little while you are going to see someone that is covered in bandages around primarily their elbows, knees, and palms. I can guarantee you that these folks were not recently involved in a mixed-martial arts competition. No, they were involved in a fight that no one wins and so many enter into every single year while traveling in Thailand. Renting motorbikes.
The thing about renting a scooter in Thailand and the last I checked it is still this way, is that they will rent them to literally anyone. They will continue to allow you to rent the bike even if you clearly exhibit qualities of someone that definitely does not know how to drive a motorbike. In one instance I was at a cafe near a moto-rental shop and I saw a girl leave the shop and immediately crash it into the curb across the street. The owner of the motorbike shop should have come over taken the keys and said that "this is not for you" but that is not what he did at all. He helped her up, gave her a tiny little tutorial and then she drove down a friggin hill and crashed into the end of that as well.
Now I don't think she was seriously hurt, but the point of the story is that these bikes, although simplistic as far as motorcycles are concerned, are not just something you can get on and know how to use immediately, and Thailand is definitely not the place you want to learn how to ride motorbikes either.
For one thing, the roads are chaos in Thailand by western standards. People drive wherever they can fit the bike. No one observes any sort of right-of-way the way that we imagine it in the west and people will drive on the wrong side of the road driving into traffic if that way is shorter.
Thailand also has one of the highest road fatality rates in the world. I personally know many people that have crashed there and one of these people will likely be a vegetable for the rest of her life. She has been for 6 years after emerging from her coma and I don't know much about how brain damage works, but I think that is past the point of no return as far as recovery is concerned.
The reason why the motorbike shops will rent to you even though you clearly can not drive a bike is because they make more money on the bike if you crash the thing that if you do not. If you return the bike all scratched up (which in the situation of the girl I mentioned above, she probably returned it all sorts of scratched up) then you will have to pay for repairs and in many situations these numbers are just pulled out of the sky. They will also argue that you have to pay for the days that the can not rent the bike because it is being repaired. If you protest, you don't need to call the police because they will do it for you. The police will not be on your side as far as this is concerned and you probably signed a contract agreeing to pay for any damages.
You are screwed in this situation because there is a really good chance that you had to leave your passport as a deposit in order to rent the bike, so fleeing is not an option either.
The combination of accidents being extremely common in Thailand, the fact that you almost certainly are not covered by insurance (for the bike) should you crash it, and the fact that road rash takes ages to heal and broken bones will end your vacation is, in my mind, a powerful combination of reason to perhaps not rent a scooter if you don't know how to drive them. This "fun little adventure and selfie moment" could cost you your life, or at best a bunch of money.
Think it over. Just because it is there doesn't mean you should do it. Taxis cost so little by using various apps these days you don't really need your own transport either.