Chemo sessions vary in length from a half hour to a couple hours to multiple days in the hospital, or an at-home pump. It just depends on what your doctor has chosen for you.
Whether you will be able to drive or not, I think depends on your overall condition. My dad had no difficulty driving with his first cancer and chemo. This time around, he needed a lot of assistance because of his overall condition. Maybe you could get a ride to your first chemo session, and see how you feel. Most likely, if you were in relatively good condition before, you may be able to drive. People react differently to their chemo. If you are feeling really crappy when you leave, make sure you tell the chemo nurses. They may be able to give you something additional to help. With dad, usually side effects didn't show up until the third day after chemo.