No, if you're talking about a continuous period of time, you need "is open." So, "The shop is open between 8am and 9pm" says that the shop is open for thirteen hours that day. "The shop opens" would refer to the specific act of someone opening for business. So "The shop opens at 8am and then remains open until 9pm. That means the shop is open between 8am and 9pm." I hope that helps!