Hi, we recently took a roadtrip, and I found it easier to try to leave around nap time that way they sleep most of the trip and they arrive rested and in a good mood :). When he was awake we were singing and try to give him toys or play with some of his stuffed animals.
We usually visit my parents about 2.5 hours away. I time the travel to be around nap time so my son sleeps the majority of the trip. I don't know how you feel about screentime but I have a tablet mount in the car so he can watch ms. Rachel or elmo during the time he's not sleep. The combo of sleep and entertainment makes the trip smooth. I also travel with his busy book in case he was to play. We typically don't make any stops since it's a short trip.