It is a great portrayal of father and daughter connecting together on road-trip her father set off to attend a college reunion. But the real reason being that he wanted her mother (his ex-wife) to take care of her because he hasn't got much time left as he has a bone tumor in his brain which has 20% of success rate if he undergoes the surgery for it.
That is just a nutshell of the movie. There's a lot of fun, emotions to be experienced when you watch the movie.
The ending of the movie will be totally unexpected, that's for sure! (this is literally mentioned at the start of the movie)
This movie really shows us that in this "GenZ", we are so lost in touch with the most important relationship in our lives - parents & their children. Parents busy with their work life and children dealing with their own phases and transitions in their life. We all really need to learn to give time to ones who dearly love us!