Thailand is a hot weather country. We suggest you to bring hot weather clothes such as t-shirt and shorts while visit Thailand.
Also, we recoomend you to bring sun protection such as sunscreen, sun glasses, hat and umbrella as the weather is very hot during midday especially on the summer.
Yes, it's possible to change itinerary if the destination is located within the route.
The driver is not a tour guide. They can give you some information as long as they know but they will not walk along and guide you while you are visiting attraction.
If you prefer a tour guide, you can make a request in a booking which there is an additional charge for hire a tour guide.
Our driver can communicate in basic English. They can help you in basic need such as direction, food and toilet. Please do not expect fluent English skill from the driver as English is not an official language in Thailand but they will help you as much as they can.